ExpandoObject Class

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Represents an object whose members can be dynamically added and removed at run time.

Inheritance Hierarchy

System.Object
  System.Dynamic.ExpandoObject

Namespace:  System.Dynamic
Assembly:  System.Core (in System.Core.dll)

Syntax

'Declaration
Public NotInheritable Class ExpandoObject _
    Implements IDynamicMetaObjectProvider, IDictionary(Of String, Object),  _
    ICollection(Of KeyValuePair(Of String, Object)), IEnumerable(Of KeyValuePair(Of String, Object)),  _
    IEnumerable, INotifyPropertyChanged

public sealed class ExpandoObject : IDynamicMetaObjectProvider, 
    IDictionary<string, Object>, ICollection<KeyValuePair<string, Object>>, 
    IEnumerable<KeyValuePair<string, Object>>, IEnumerable, INotifyPropertyChanged

The ExpandoObject type exposes the following members.

Constructors

	Name	Description
	ExpandoObject	Initializes a new ExpandoObject that does not have members.

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Methods

	Name	Description
	Equals(Object)	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)

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Extension Methods

	Name	Description
	Aggregate<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, KeyValuePair<String, Object>, KeyValuePair<String, Object>>)	Overloaded. Applies an accumulator function over a sequence. (Defined by Enumerable.)
	Aggregate<KeyValuePair<String, Object>, TAccumulate>(TAccumulate, Func<TAccumulate, KeyValuePair<String, Object>, TAccumulate>)	Overloaded. Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value. (Defined by Enumerable.)
	Aggregate<KeyValuePair<String, Object>, TAccumulate, TResult>(TAccumulate, Func<TAccumulate, KeyValuePair<String, Object>, TAccumulate>, Func<TAccumulate, TResult>)	Overloaded. Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value, and the specified function is used to select the result value. (Defined by Enumerable.)
	All<KeyValuePair<String, Object>>	Determines whether all elements of a sequence satisfy a condition. (Defined by Enumerable.)
	Any<KeyValuePair<String, Object>>()	Overloaded. Determines whether a sequence contains any elements. (Defined by Enumerable.)
	Any<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Determines whether any element of a sequence satisfies a condition. (Defined by Enumerable.)
	AsEnumerable<KeyValuePair<String, Object>>	Returns the input typed as IEnumerable<T>. (Defined by Enumerable.)
	AsQueryable()	Overloaded. Converts an IEnumerable to an IQueryable. (Defined by Queryable.)
	AsQueryable<KeyValuePair<String, Object>>()	Overloaded. Converts a generic IEnumerable<T> to a generic IQueryable<T>. (Defined by Queryable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Decimal>>)	Overloaded. Computes the average of a sequence of nullable Decimal values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Double>>)	Overloaded. Computes the average of a sequence of nullable Double values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int32>)	Overloaded. Computes the average of a sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Int32>>)	Overloaded. Computes the average of a sequence of nullable Int32 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int64>)	Overloaded. Computes the average of a sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Int64>>)	Overloaded. Computes the average of a sequence of nullable Int64 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Single>)	Overloaded. Computes the average of a sequence of Single values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Single>>)	Overloaded. Computes the average of a sequence of nullable Single values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Double>)	Overloaded. Computes the average of a sequence of Double values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Average<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Decimal>)	Overloaded. Computes the average of a sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Cast<TResult>	Converts the elements of an IEnumerable to the specified type. (Defined by Enumerable.)
	Concat<KeyValuePair<String, Object>>	Concatenates two sequences. (Defined by Enumerable.)
	Contains<KeyValuePair<String, Object>>(KeyValuePair<String, Object>)	Overloaded. Determines whether a sequence contains a specified element by using the default equality comparer. (Defined by Enumerable.)
	Contains<KeyValuePair<String, Object>>(KeyValuePair<String, Object>, IEqualityComparer<KeyValuePair<String, Object>>)	Overloaded. Determines whether a sequence contains a specified element by using a specified IEqualityComparer<T>. (Defined by Enumerable.)
	Count<KeyValuePair<String, Object>>()	Overloaded. Returns the number of elements in a sequence. (Defined by Enumerable.)
	Count<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Returns a number that represents how many elements in the specified sequence satisfy a condition. (Defined by Enumerable.)
	DefaultIfEmpty<KeyValuePair<String, Object>>()	Overloaded. Returns the elements of the specified sequence or the type parameter's default value in a singleton collection if the sequence is empty. (Defined by Enumerable.)
	DefaultIfEmpty<KeyValuePair<String, Object>>(KeyValuePair<String, Object>)	Overloaded. Returns the elements of the specified sequence or the specified value in a singleton collection if the sequence is empty. (Defined by Enumerable.)
	Distinct<KeyValuePair<String, Object>>()	Overloaded. Returns distinct elements from a sequence by using the default equality comparer to compare values. (Defined by Enumerable.)
	Distinct<KeyValuePair<String, Object>>(IEqualityComparer<KeyValuePair<String, Object>>)	Overloaded. Returns distinct elements from a sequence by using a specified IEqualityComparer<T> to compare values. (Defined by Enumerable.)
	ElementAt<KeyValuePair<String, Object>>	Returns the element at a specified index in a sequence. (Defined by Enumerable.)
	ElementAtOrDefault<KeyValuePair<String, Object>>	Returns the element at a specified index in a sequence or a default value if the index is out of range. (Defined by Enumerable.)
	Except<KeyValuePair<String, Object>>(IEnumerable<KeyValuePair<String, Object>>)	Overloaded. Produces the set difference of two sequences by using the default equality comparer to compare values. (Defined by Enumerable.)
	Except<KeyValuePair<String, Object>>(IEnumerable<KeyValuePair<String, Object>>, IEqualityComparer<KeyValuePair<String, Object>>)	Overloaded. Produces the set difference of two sequences by using the specified IEqualityComparer<T> to compare values. (Defined by Enumerable.)
	First<KeyValuePair<String, Object>>()	Overloaded. Returns the first element of a sequence. (Defined by Enumerable.)
	First<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Returns the first element in a sequence that satisfies a specified condition. (Defined by Enumerable.)
	FirstOrDefault<KeyValuePair<String, Object>>()	Overloaded. Returns the first element of a sequence, or a default value if the sequence contains no elements. (Defined by Enumerable.)
	FirstOrDefault<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Returns the first element of the sequence that satisfies a condition or a default value if no such element is found. (Defined by Enumerable.)
	GroupBy<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>)	Overloaded. Groups the elements of a sequence according to a specified key selector function. (Defined by Enumerable.)
	GroupBy<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>, IEqualityComparer<TKey>)	Overloaded. Groups the elements of a sequence according to a specified key selector function and compares the keys by using a specified comparer. (Defined by Enumerable.)
	GroupBy<KeyValuePair<String, Object>, TKey, TElement>(Func<KeyValuePair<String, Object>, TKey>, Func<KeyValuePair<String, Object>, TElement>)	Overloaded. Groups the elements of a sequence according to a specified key selector function and projects the elements for each group by using a specified function. (Defined by Enumerable.)
	GroupBy<KeyValuePair<String, Object>, TKey, TResult>(Func<KeyValuePair<String, Object>, TKey>, Func<TKey, IEnumerable<KeyValuePair<String, Object>>, TResult>)	Overloaded. Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. (Defined by Enumerable.)
	GroupBy<KeyValuePair<String, Object>, TKey, TElement>(Func<KeyValuePair<String, Object>, TKey>, Func<KeyValuePair<String, Object>, TElement>, IEqualityComparer<TKey>)	Overloaded. Groups the elements of a sequence according to a key selector function. The keys are compared by using a comparer and each group's elements are projected by using a specified function. (Defined by Enumerable.)
	GroupBy<KeyValuePair<String, Object>, TKey, TResult>(Func<KeyValuePair<String, Object>, TKey>, Func<TKey, IEnumerable<KeyValuePair<String, Object>>, TResult>, IEqualityComparer<TKey>)	Overloaded. Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The keys are compared by using a specified comparer. (Defined by Enumerable.)
	GroupBy<KeyValuePair<String, Object>, TKey, TElement, TResult>(Func<KeyValuePair<String, Object>, TKey>, Func<KeyValuePair<String, Object>, TElement>, Func<TKey, IEnumerable<TElement>, TResult>)	Overloaded. Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The elements of each group are projected by using a specified function. (Defined by Enumerable.)
	GroupBy<KeyValuePair<String, Object>, TKey, TElement, TResult>(Func<KeyValuePair<String, Object>, TKey>, Func<KeyValuePair<String, Object>, TElement>, Func<TKey, IEnumerable<TElement>, TResult>, IEqualityComparer<TKey>)	Overloaded. Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. Key values are compared by using a specified comparer, and the elements of each group are projected by using a specified function. (Defined by Enumerable.)
	GroupJoin<KeyValuePair<String, Object>, TInner, TKey, TResult>(IEnumerable<TInner>, Func<KeyValuePair<String, Object>, TKey>, Func<TInner, TKey>, Func<KeyValuePair<String, Object>, IEnumerable<TInner>, TResult>)	Overloaded. Correlates the elements of two sequences based on equality of keys and groups the results. The default equality comparer is used to compare keys. (Defined by Enumerable.)
	GroupJoin<KeyValuePair<String, Object>, TInner, TKey, TResult>(IEnumerable<TInner>, Func<KeyValuePair<String, Object>, TKey>, Func<TInner, TKey>, Func<KeyValuePair<String, Object>, IEnumerable<TInner>, TResult>, IEqualityComparer<TKey>)	Overloaded. Correlates the elements of two sequences based on key equality and groups the results. A specified IEqualityComparer<T> is used to compare keys. (Defined by Enumerable.)
	Intersect<KeyValuePair<String, Object>>(IEnumerable<KeyValuePair<String, Object>>)	Overloaded. Produces the set intersection of two sequences by using the default equality comparer to compare values. (Defined by Enumerable.)
	Intersect<KeyValuePair<String, Object>>(IEnumerable<KeyValuePair<String, Object>>, IEqualityComparer<KeyValuePair<String, Object>>)	Overloaded. Produces the set intersection of two sequences by using the specified IEqualityComparer<T> to compare values. (Defined by Enumerable.)
	Join<KeyValuePair<String, Object>, TInner, TKey, TResult>(IEnumerable<TInner>, Func<KeyValuePair<String, Object>, TKey>, Func<TInner, TKey>, Func<KeyValuePair<String, Object>, TInner, TResult>)	Overloaded. Correlates the elements of two sequences based on matching keys. The default equality comparer is used to compare keys. (Defined by Enumerable.)
	Join<KeyValuePair<String, Object>, TInner, TKey, TResult>(IEnumerable<TInner>, Func<KeyValuePair<String, Object>, TKey>, Func<TInner, TKey>, Func<KeyValuePair<String, Object>, TInner, TResult>, IEqualityComparer<TKey>)	Overloaded. Correlates the elements of two sequences based on matching keys. A specified IEqualityComparer<T> is used to compare keys. (Defined by Enumerable.)
	Last<KeyValuePair<String, Object>>()	Overloaded. Returns the last element of a sequence. (Defined by Enumerable.)
	Last<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Returns the last element of a sequence that satisfies a specified condition. (Defined by Enumerable.)
	LastOrDefault<KeyValuePair<String, Object>>()	Overloaded. Returns the last element of a sequence, or a default value if the sequence contains no elements. (Defined by Enumerable.)
	LastOrDefault<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Returns the last element of a sequence that satisfies a condition or a default value if no such element is found. (Defined by Enumerable.)
	LongCount<KeyValuePair<String, Object>>()	Overloaded. Returns an Int64 that represents the total number of elements in a sequence. (Defined by Enumerable.)
	LongCount<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Returns an Int64 that represents how many elements in a sequence satisfy a condition. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>()	Overloaded. Returns the maximum value in a generic sequence. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Decimal>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Decimal value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Double>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Double value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int32>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Int32 value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Int32>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Int32 value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int64>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Int64 value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Int64>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Int64 value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Single>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Single value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Single>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Single value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Double>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Double value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Decimal>)	Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Decimal value. (Defined by Enumerable.)
	Max<KeyValuePair<String, Object>, TResult>(Func<KeyValuePair<String, Object>, TResult>)	Overloaded. Invokes a transform function on each element of a generic sequence and returns the maximum resulting value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>()	Overloaded. Returns the minimum value in a generic sequence. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Decimal>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Decimal value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Double>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Double value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int32>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Int32 value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Int32>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Int32 value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int64>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Int64 value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Int64>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Int64 value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Single>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Single value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Single>>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Single value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Double>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Double value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Decimal>)	Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Decimal value. (Defined by Enumerable.)
	Min<KeyValuePair<String, Object>, TResult>(Func<KeyValuePair<String, Object>, TResult>)	Overloaded. Invokes a transform function on each element of a generic sequence and returns the minimum resulting value. (Defined by Enumerable.)
	OfType<TResult>	Filters the elements of an IEnumerable based on a specified type. (Defined by Enumerable.)
	OrderBy<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>)	Overloaded. Sorts the elements of a sequence in ascending order according to a key. (Defined by Enumerable.)
	OrderBy<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>, IComparer<TKey>)	Overloaded. Sorts the elements of a sequence in ascending order by using a specified comparer. (Defined by Enumerable.)
	OrderByDescending<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>)	Overloaded. Sorts the elements of a sequence in descending order according to a key. (Defined by Enumerable.)
	OrderByDescending<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>, IComparer<TKey>)	Overloaded. Sorts the elements of a sequence in descending order by using a specified comparer. (Defined by Enumerable.)
	Reverse<KeyValuePair<String, Object>>	Inverts the order of the elements in a sequence. (Defined by Enumerable.)
	Select<KeyValuePair<String, Object>, TResult>(Func<KeyValuePair<String, Object>, TResult>)	Overloaded. Projects each element of a sequence into a new form. (Defined by Enumerable.)
	Select<KeyValuePair<String, Object>, TResult>(Func<KeyValuePair<String, Object>, Int32, TResult>)	Overloaded. Projects each element of a sequence into a new form by incorporating the element's index. (Defined by Enumerable.)
	SelectMany<KeyValuePair<String, Object>, TResult>(Func<KeyValuePair<String, Object>, IEnumerable<TResult>>)	Overloaded. Projects each element of a sequence to an IEnumerable<T> and flattens the resulting sequences into one sequence. (Defined by Enumerable.)
	SelectMany<KeyValuePair<String, Object>, TResult>(Func<KeyValuePair<String, Object>, Int32, IEnumerable<TResult>>)	Overloaded. Projects each element of a sequence to an IEnumerable<T>, and flattens the resulting sequences into one sequence. The index of each source element is used in the projected form of that element. (Defined by Enumerable.)
	SelectMany<KeyValuePair<String, Object>, TCollection, TResult>(Func<KeyValuePair<String, Object>, Int32, IEnumerable<TCollection>>, Func<KeyValuePair<String, Object>, TCollection, TResult>)	Overloaded. Projects each element of a sequence to an IEnumerable<T>, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein. The index of each source element is used in the intermediate projected form of that element. (Defined by Enumerable.)
	SelectMany<KeyValuePair<String, Object>, TCollection, TResult>(Func<KeyValuePair<String, Object>, IEnumerable<TCollection>>, Func<KeyValuePair<String, Object>, TCollection, TResult>)	Overloaded. Projects each element of a sequence to an IEnumerable<T>, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein. (Defined by Enumerable.)
	SequenceEqual<KeyValuePair<String, Object>>(IEnumerable<KeyValuePair<String, Object>>)	Overloaded. Determines whether two sequences are equal by comparing the elements by using the default equality comparer for their type. (Defined by Enumerable.)
	SequenceEqual<KeyValuePair<String, Object>>(IEnumerable<KeyValuePair<String, Object>>, IEqualityComparer<KeyValuePair<String, Object>>)	Overloaded. Determines whether two sequences are equal by comparing their elements by using a specified IEqualityComparer<T>. (Defined by Enumerable.)
	Single<KeyValuePair<String, Object>>()	Overloaded. Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence. (Defined by Enumerable.)
	Single<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists. (Defined by Enumerable.)
	SingleOrDefault<KeyValuePair<String, Object>>()	Overloaded. Returns the only element of a sequence, or a default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence. (Defined by Enumerable.)
	SingleOrDefault<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Returns the only element of a sequence that satisfies a specified condition or a default value if no such element exists; this method throws an exception if more than one element satisfies the condition. (Defined by Enumerable.)
	Skip<KeyValuePair<String, Object>>	Bypasses a specified number of elements in a sequence and then returns the remaining elements. (Defined by Enumerable.)
	SkipWhile<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements. (Defined by Enumerable.)
	SkipWhile<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int32, Boolean>)	Overloaded. Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements. The element's index is used in the logic of the predicate function. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Decimal>>)	Overloaded. Computes the sum of the sequence of nullable Decimal values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Double>>)	Overloaded. Computes the sum of the sequence of nullable Double values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int32>)	Overloaded. Computes the sum of the sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Int32>>)	Overloaded. Computes the sum of the sequence of nullable Int32 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int64>)	Overloaded. Computes the sum of the sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Int64>>)	Overloaded. Computes the sum of the sequence of nullable Int64 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Single>)	Overloaded. Computes the sum of the sequence of Single values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Nullable<Single>>)	Overloaded. Computes the sum of the sequence of nullable Single values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Double>)	Overloaded. Computes the sum of the sequence of Double values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Sum<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Decimal>)	Overloaded. Computes the sum of the sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
	Take<KeyValuePair<String, Object>>	Returns a specified number of contiguous elements from the start of a sequence. (Defined by Enumerable.)
	TakeWhile<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Returns elements from a sequence as long as a specified condition is true. (Defined by Enumerable.)
	TakeWhile<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int32, Boolean>)	Overloaded. Returns elements from a sequence as long as a specified condition is true. The element's index is used in the logic of the predicate function. (Defined by Enumerable.)
	ToArray<KeyValuePair<String, Object>>	Creates an array from a IEnumerable<T>. (Defined by Enumerable.)
	ToDictionary<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>)	Overloaded. Creates a Dictionary<TKey, TValue> from an IEnumerable<T> according to a specified key selector function. (Defined by Enumerable.)
	ToDictionary<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>, IEqualityComparer<TKey>)	Overloaded. Creates a Dictionary<TKey, TValue> from an IEnumerable<T> according to a specified key selector function and key comparer. (Defined by Enumerable.)
	ToDictionary<KeyValuePair<String, Object>, TKey, TElement>(Func<KeyValuePair<String, Object>, TKey>, Func<KeyValuePair<String, Object>, TElement>)	Overloaded. Creates a Dictionary<TKey, TValue> from an IEnumerable<T> according to specified key selector and element selector functions. (Defined by Enumerable.)
	ToDictionary<KeyValuePair<String, Object>, TKey, TElement>(Func<KeyValuePair<String, Object>, TKey>, Func<KeyValuePair<String, Object>, TElement>, IEqualityComparer<TKey>)	Overloaded. Creates a Dictionary<TKey, TValue> from an IEnumerable<T> according to a specified key selector function, a comparer, and an element selector function. (Defined by Enumerable.)
	ToList<KeyValuePair<String, Object>>	Creates a List<T> from an IEnumerable<T>. (Defined by Enumerable.)
	ToLookup<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>)	Overloaded. Creates a Lookup<TKey, TElement> from an IEnumerable<T> according to a specified key selector function. (Defined by Enumerable.)
	ToLookup<KeyValuePair<String, Object>, TKey>(Func<KeyValuePair<String, Object>, TKey>, IEqualityComparer<TKey>)	Overloaded. Creates a Lookup<TKey, TElement> from an IEnumerable<T> according to a specified key selector function and key comparer. (Defined by Enumerable.)
	ToLookup<KeyValuePair<String, Object>, TKey, TElement>(Func<KeyValuePair<String, Object>, TKey>, Func<KeyValuePair<String, Object>, TElement>)	Overloaded. Creates a Lookup<TKey, TElement> from an IEnumerable<T> according to specified key selector and element selector functions. (Defined by Enumerable.)
	ToLookup<KeyValuePair<String, Object>, TKey, TElement>(Func<KeyValuePair<String, Object>, TKey>, Func<KeyValuePair<String, Object>, TElement>, IEqualityComparer<TKey>)	Overloaded. Creates a Lookup<TKey, TElement> from an IEnumerable<T> according to a specified key selector function, a comparer and an element selector function. (Defined by Enumerable.)
	Union<KeyValuePair<String, Object>>(IEnumerable<KeyValuePair<String, Object>>)	Overloaded. Produces the set union of two sequences by using the default equality comparer. (Defined by Enumerable.)
	Union<KeyValuePair<String, Object>>(IEnumerable<KeyValuePair<String, Object>>, IEqualityComparer<KeyValuePair<String, Object>>)	Overloaded. Produces the set union of two sequences by using a specified IEqualityComparer<T>. (Defined by Enumerable.)
	Where<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Boolean>)	Overloaded. Filters a sequence of values based on a predicate. (Defined by Enumerable.)
	Where<KeyValuePair<String, Object>>(Func<KeyValuePair<String, Object>, Int32, Boolean>)	Overloaded. Filters a sequence of values based on a predicate. Each element's index is used in the logic of the predicate function. (Defined by Enumerable.)
	Zip<KeyValuePair<String, Object>, TSecond, TResult>	Merges two sequences by using the specified predicate function. (Defined by Enumerable.)

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Explicit Interface Implementations

	Name	Description
	ICollection<KeyValuePair<String, Object>>.Add	Adds the specified value to the ICollection<T> that has the specified key.
	ICollection<KeyValuePair<String, Object>>.Clear	Removes all items from the collection.
	ICollection<KeyValuePair<String, Object>>.Contains	Determines whether the ICollection<T> contains a specific key and value.
	ICollection<KeyValuePair<String, Object>>.CopyTo	Copies the elements of the ICollection<T> to an array of type KeyValuePair<TKey, TValue>, starting at the specified array index.
	ICollection<KeyValuePair<String, Object>>.Count	Gets the number of elements in the ICollection<T>.
	ICollection<KeyValuePair<String, Object>>.IsReadOnly	Gets a value indicating whether the ICollection<T> is read-only.
	ICollection<KeyValuePair<String, Object>>.Remove	Removes a key and value from the collection.
	IDictionary<String, Object>.Add	Adds the specified key and value to the dictionary.
	IDictionary<String, Object>.ContainsKey	Determines whether the dictionary contains the specified key.
	IDictionary<String, Object>.Item	Gets or sets the element that has the specified key.
	IDictionary<String, Object>.Keys	Gets an ICollection<T> that contains the keys of the IDictionary<TKey, TValue>.
	IDictionary<String, Object>.Remove	Removes the element that has the specified key from the IDictionary.
	IDictionary<String, Object>.TryGetValue	Gets the value associated with the specified key.
	IDictionary<String, Object>.Values	Gets an ICollection<T> that contains the values in the IDictionary<TKey, TValue>.
	IDynamicMetaObjectProvider.GetMetaObject	The provided MetaObject will dispatch to the dynamic virtual methods. The object can be encapsulated inside another MetaObject to provide custom behavior for individual actions.
	IEnumerable<KeyValuePair<String, Object>>.GetEnumerator	Returns an enumerator that iterates through the collection.
	IEnumerable.GetEnumerator	Returns an enumerator that iterates through the collection.
	INotifyPropertyChanged.PropertyChanged	Occurs when a property value changes.

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Remarks

The ExpandoObject class enables you to add and delete members of its instances at run time and also to set and get values of these members. This class supports dynamic binding, which enables you to use standard syntax like sampleObject.sampleMember instead of more complex syntax like sampleObject.GetAttribute("sampleMember").

The ExpandoObject class implements the standard Dynamic Language Runtime (DLR) interface IDynamicMetaObjectProvider, which enables you to share instances of the ExpandoObject class between languages that support the DLR interoperability model. For example, you can create an instance of the ExpandoObject class in C# and then pass it to an IronPython function. For more information, see documentation on the CodePlex Web site, and Introducing the ExpandoObject on the C# Frequently Asked Questions Web site.

The ExpandoObject class is an implementation of the dynamic object concept that enables getting, setting, and invoking members. If you want to define types that have their own dynamic dispatch semantics, use the DynamicObject class. If you want to define how dynamic objects participate in the interoperability protocol and manage DLR fast dynamic dispatch caching, create your own implementation of the IDynamicMetaObjectProvider interface.

Creating an Instance

In C#, to enable late binding for an instance of the ExpandoObject class, you must use the dynamic keyword.

In Visual Basic, dynamic operations are supported by late binding.

The following code example demonstrates how to create an instance of the ExpandoObject class.

Dim sampleObject As Object = New ExpandoObject()

dynamic sampleObject = new ExpandoObject();

Adding New Members

You can add properties, methods, and events to instances of the ExpandoObject class.

The following code example demonstrates how to add a new property to an instance of the ExpandoObject class.

sampleObject.Test = "Dynamic Property"
outputBlock.Text &= sampleObject.test & vbCrLf
outputBlock.Text &= sampleObject.test.GetType().ToString() & vbCrLf
' This code example produces the following output:
' Dynamic Property
' System.String

sampleObject.test = "Dynamic Property";
outputBlock.Text += sampleObject.test + "\n";
outputBlock.Text += sampleObject.test.GetType() + "\n";
// This code example produces the following output:
// Dynamic Property
// System.String

The methods represent lambda expressions that are stored as delegates, which can be invoked when they are needed. The following code example demonstrates how to add a method that increments a value of the dynamic property.

sampleObject.Number = 10
sampleObject.Increment = Function() sampleObject.Number + 1
' Before calling the Increment method.
outputBlock.Text &= sampleObject.number & vbCrLf

sampleObject.Increment.Invoke()

' After calling the Increment method.
outputBlock.Text &= sampleObject.number & vbCrLf
' This code example produces the following output:
' 10
' 11

sampleObject.number = 10;
sampleObject.Increment = (Action)(() => { sampleObject.number++; });

// Before calling the Increment method.
outputBlock.Text += sampleObject.number + "\n";

sampleObject.Increment();

// After calling the Increment method.
outputBlock.Text += sampleObject.number + "\n";
// This code example produces the following output:
// 10
// 11

The following code example demonstrates how to add an event to an instance of the ExpandoObject class.

class Program
{
    static void Main(string[] args)
    {
        dynamic sampleObject = new ExpandoObject();

        // Create a new event and initialize it with null.
        sampleObject.sampleEvent = null;

        // Add an event handler.
        sampleObject.sampleEvent += new EventHandler(SampleHandler);

        // Raise an event for testing purposes.
        sampleObject.sampleEvent(sampleObject, new EventArgs());
   }

    // Event handler.
    static void SampleHandler(object sender, EventArgs e)
    {
        outputBlock.Text = "SampleHandler for " + sender + "event\n";
    }
}
// This code example produces the following output:
// SampleHandler for System.Dynamic.ExpandoObject event.

Module Module1

Sub Main()
    Dim sampleObject As Object = New ExpandoObject()

    ' Create a new event and initialize it with null.
    sampleObject.sampleEvent = Nothing

    ' Add an event handler.
    Dim handler As EventHandler = AddressOf SampleHandler
    sampleObject.sampleEvent = 
        [Delegate].Combine(sampleObject.sampleEvent, handler)

    ' Raise an event for testing purposes.
    sampleObject.sampleEvent.Invoke(sampleObject, New EventArgs())

End Sub

' Event handler.
Sub SampleHandler(ByVal sender As Object, ByVal e As EventArgs)
    outputBlock.Text = "SampleHandler for " & sender & "event" & vbCrLf
End Sub

' This code example produces the following output:
' SampleHandler for System.Dynamic.ExpandoObject event.

End Module

Passing As a Parameter

You can pass instances of the ExpandoObject class as parameters. Note that these instances are treated as dynamic objects in C# and late-bound objects in Visual Basic. This means that you do not have IntelliSense for object members and you do not receive compiler errors when you call non-existent members. If you call a member that does not exist, an exception occurs.

The following code example demonstrates how you can create and use a method to print the names and values of properties.

Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
   Dim employee, manager As Object

   employee = New ExpandoObject()
   employee.Name = "John Smith"
   employee.Age = 33

   manager = New ExpandoObject()
   manager.Name = "Allison Brown"
   manager.Age = 42
   manager.TeamSize = 10

   WritePerson(outputBlock, manager)
   WritePerson(outputBlock, employee)
End Sub

Private Sub WritePerson(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal person As Object)

     outputBlock.Text += String.Format("{0} is {1} years old.", _
                       person.Name, person.Age) + vbCrLf
   ' The following statement causes an exception
   ' if you pass the employee object.
   ' outputBlock.Text += String.Format("Manages {0} people", person.TeamSize) & vbCrLf

End Sub

class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      dynamic employee, manager;

      employee = new ExpandoObject();
      employee.Name = "John Smith";
      employee.Age = 33;

      manager = new ExpandoObject();
      manager.Name = "Allison Brown";
      manager.Age = 42;
      manager.TeamSize = 10;

      WritePerson(outputBlock, manager);
      WritePerson(outputBlock, employee);
   }
   private static void WritePerson(System.Windows.Controls.TextBlock outputBlock, dynamic person)
   {
      outputBlock.Text += String.Format("{0} is {1} years old.\n",
                        person.Name, person.Age);
      // The following statement causes an exception
      // if you pass the employee object.
      // outputBlock.Text += String.Format("Manages {0} people\n", person.TeamSize);
   }
}
// This code example produces the following output:
// John Smith is 33 years old.
// Allison Brown is 42 years old.

Enumerating and Deleting Members

The ExpandoObject class implements the IDictionary<String, Object> interface. This enables enumeration of members added to the instance of the ExpandoObject class at run time. This can be useful if you do not know at compile time what members an instance might have.

The following code example shows how you can cast an instance of the ExpandoObject class to the IDictionary<TKey, TValue> interface and enumerate the instance's members.

Dim employee As Object = New ExpandoObject()
employee.Name = "John Smith"
employee.Age = 33
For Each member In CType(employee, IDictionary(Of String, Object))
   outputBlock.Text &= member.Key & ": " & member.Value & vbCrLf
Next
' This code example produces the following output:
' Name: John Smith
' Age: 33

dynamic employee = new ExpandoObject();
employee.Name = "John Smith";
employee.Age = 33;

foreach (var property in (IDictionary<String, Object>)employee)
{
   outputBlock.Text += property.Key + ": " + property.Value + "\n";
}
// This code example produces the following output:
// Name: John Smith
// Age: 33

In languages that do not have syntax for deleting members (such as C# and Visual Basic), you can delete a member by implicitly casting an instance of the ExpandoObject to the IDictionary<String, Object> interface and then deleting the member as a key/value pair. This is shown in the following example.

Dim employee As Object = New ExpandoObject()
employee.Name = "John Smith"
  CType(employee, IDictionary(Of String, Object)).Remove("Name")

dynamic employee = new ExpandoObject();
employee.Name = "John Smith";
((IDictionary<String, Object>)employee).Remove("Name");

Receiving Notifications of Property Changes

The ExpandoObject class implements the INotifyPropertyChanged interface and can raise a PropertyChanged event when a member is added, deleted, or modified. This enables ExpandoObject class integration with Windows Presentation Foundation (WPF) data binding and other environments that require notification about changes in the object content.

The following code example demonstrates how to create an event handler for the PropertyChanged event.

' Add "Imports System.ComponentModel" line 
' to the beginning of the file.
Sub Main(outputBlock As System.Windows.Controls.TextBlock)
   Dim employee As Object = New ExpandoObject
     AddHandler CType(employee, INotifyPropertyChanged).PropertyChanged, _
         AddressOf HandlePropertyChanges
   employee.Name = "John Smith"
End Sub

 Private Sub HandlePropertyChanges(ByVal sender As Object, ByVal e As PropertyChangedEventArgs)
   outputBlock.Text += String.Format("{0} has changed.", e.PropertyName) & vbCrLf
End Sub

// Add "using System.ComponentModel;" line 
// to the beginning of the file.
class Program
{
   static System.Windows.Controls.TextBlock outputBlock;

   static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      Program.outputBlock = outputBlock;

      dynamic employee = new ExpandoObject();
      ((INotifyPropertyChanged)employee).PropertyChanged +=
          new PropertyChangedEventHandler(HandlePropertyChanges);
      employee.Name = "John Smith";
   }

   private static void HandlePropertyChanges(
       object sender, PropertyChangedEventArgs e)
   {
      outputBlock.Text += String.Format("{0} has changed.", e.PropertyName) + "\n";
   }
}

Version Information

Silverlight

Supported in: 5, 4

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

See Also

Reference

System.Dynamic Namespace