Platform::Collections::Vector Class
Represents a sequential collection of objects that can be individually accessed by index. Implements Windows::Foundation::Collections::IObservableVector to help with XAML data binding.
Syntax
template <typename T, typename E>
ref class Vector sealed;
Parameters
T
The type of the elements contained in the Vector object.
E
Specifies a binary predicate for testing equality with values of type T. The default value is std::equal_to<T>.
Remarks
Allowed types are:
integers
interface class^
public ref class^
value struct
public enum class
The Vector class is the C++ concrete implementation of the Windows::Foundation::Collections::IVector interface.
If you attempt to use a Vector type in a public return value or parameter, compiler error C3986 is raised. You can fix the error by changing the parameter or return value type to Windows::Foundation::Collections::IVector. For more information, see Collections (C++/CX).
Members
Public Constructors
| Name | Description |
|---|---|
| Vector::Vector | Initializes a new instance of the Vector class. |
Public Methods
| Name | Description |
|---|---|
| Vector::Append | Inserts the specified item after the last item in the current Vector. |
| Vector::Clear | Deletes all the elements in the current Vector. |
| Vector::First | Returns an iterator that specifies the first element in the Vector. |
| Vector::GetAt | Retrieves the element of the current Vector that is identifed by the specified index. |
| Vector::GetMany | Retrieves a sequence of items from the current Vector, starting at the specified index. |
| Vector::GetView | Returns a read-only view of a Vector; that is, a Platform::Collections::VectorView. |
| Vector::IndexOf | Searches for the specified item in the current Vector, and if found, returns the index of the item. |
| Vector::InsertAt | Inserts the specified item into the current Vector at the element identified by the specified index. |
| Vector::ReplaceAll | Deletes the elements in the current Vector and then inserts the elements from the specified array. |
| Vector::RemoveAt | Deletes the element identified by the specified index from the current Vector. |
| Vector::RemoveAtEnd | Deletes the element at the end of the current Vector. |
| Vector::SetAt | Assigns the specified value to the element in the current Vector that is identified by the specified index. |
| Vector::Size | Returns the number of elements in the current Vector object. |
Events
| Name | Description |
|---|---|
| event Windows::Foundation::Collection::VectorChangedEventHandler<T>^ VectorChanged | Occurs when the Vector changes. |
Inheritance Hierarchy
Vector
Requirements
Header: collection.h
Namespace: Platform::Collections
Vector::Append Method
Inserts the specified item after the last item in the current Vector.
Syntax
virtual void Append(T item);
Parameters
index
The item to insert into the Vector. The type of item is defined by the T typename.
Vector::Clear Method
Deletes all the elements in the current Vector.
Syntax
virtual void Clear();
Vector::First Method
Returns an iterator that points to the first element in the Vector.
Syntax
virtual Windows::Foundation::Collections::IIterator <T>^ First();
Return Value
An iterator that points to the first element in the Vector.
Remarks
A convenient way to hold the iterator returned by First() is to assign the return value to a variable that is declared with the auto type deduction keyword. For example, auto x = myVector->First();. This iterator knows the length of the collection.
When you need a pair of iterators to pass to an STL function, use the free functions Windows::Foundation::Collections::begin and Windows::Foundation::Collections::end
Vector::GetAt Method
Retrieves the element of the current Vector that is identifed by the specified index.
Syntax
virtual T GetAt(unsigned int index);
Parameters
index
A zero-based, unsigned integer that specifies a particular element in the Vector object.
Return Value
The element specified by the index parameter. The element type is defined by the T typename.
Vector::GetMany Method
Retrieves a sequence of items from the current Vector, starting at the specified index, and copies them into the caller-allocated array.
Syntax
virtual unsigned int GetMany(
unsigned int startIndex,
Platform::WriteOnlyArray<T>^ dest);
Parameters
startIndex
The zero-based index of the start of the items to retrieve.
dest
A caller-allocated array of items that begin at the element specified by startIndex and end at the last element in the Vector.
Return Value
The number of items retrieved.
Remarks
This function is not intended for use directly by client code. It is used internally in the to_vector Function to enable efficient conversion of Platform::Vector intances to std::vector instances.
Vector::GetView Method
Returns a read-only view of a Vector; that is, an IVectorView.
Syntax
Windows::Foundation::Collections::IVectorView<T>^ GetView();
Return Value
An IVectorView object.
Vector::IndexOf Method
Searches for the specified item in the current Vector, and if found, returns the index of the item.
Syntax
virtual bool IndexOf(T value, unsigned int* index);
Parameters
value
The item to find.
index
The zero-based index of the item if parameter value is found; otherwise, 0.
The index parameter is 0 if either the item is the first element of the Vector or the item was not found. If the return value is true, the item was found and it is the first element; otherwise, the item was not found.
Return Value
true if the specified item is found; otherwise, false.
Remarks
IndexOf uses std::find_if to find the item. Custom element types should therefore overload the == and != operator in order to enable the equality comparisons that find_if requires.
Vector::InsertAt Method
Inserts the specified item into the current Vector at the element identified by the specified index.
Syntax
virtual void InsertAt(unsigned int index, T item)
Parameters
index
A zero-based, unsigned integer that specifies a particular element in the Vector object.
item
An item to insert into the Vector at the element specified by index. The type of item is defined by the T typename.
Vector::RemoveAt Method
Deletes the element identified by the specified index from the current Vector.
Syntax
virtual void RemoveAt(unsigned int index);
Parameters
index
A zero-based, unsigned integer that specifies a particular element in the Vector object.
Vector::RemoveAtEnd Method
Deletes the element at the end of the current Vector.
Syntax
virtual void RemoveAtEnd();
Vector::ReplaceAll Method
Deletes the elements in the current Vector and then inserts the elements from the specified array.
Syntax
virtual void ReplaceAll(const ::Platform::Array<T>^ arr);
Parameters
arr
An array of objects whose type is defined by the T typename.
Vector::SetAt Method
Assigns the specified value to the element in the current Vector that is identified by the specified index.
Syntax
virtual void SetAt(unsigned int index, T item);
Parameters
index
A zero-based, unsigned integer that specifies a particular element in the Vector object.
item
The value to assign to the specified element. The type of item is defined by the T typename.
Vector::Size Method
Returns the number of elements in the current Vector object.
Syntax
virtual property unsigned int Size;
Return Value
The number of elements in the current Vector.
Vector::Vector Constructor
Initializes a new instance of the Vector class.
Syntax
Vector();
explicit Vector(unsigned int size);
Vector( unsigned int size, T value);
template <typename U> explicit Vector( const ::std::vector<U>& v);
template <typename U> explicit Vector( std::vector<U>&& v);
Vector( const T * ptr, unsigned int size);
template <size_t N> explicit Vector(const T(&arr)[N]);
template <size_t N> explicit Vector(const std::array<T, N>& a);
explicit Vector(const Array<T>^ arr);
template <typename InIt> Vector(InIt first, InIt last);
Vector(std::initializer_list<T> il);
Parameters
a
A std::array that will be used to initialize the Vector.
arr
A Platform::Array that will be used to initialize the Vector.
InIt
The type of a collection of objects that is used to initialize the current Vector.
il
A std::initializer_list of objects of type T that will be used to initialize the Vector.
N
The number of elements in a collection of objects that is used to initialize the current Vector.
size
The number of elements in the Vector.
value
A value that is used to initialize each element in the current Vector.
v
An Lvalues and Rvalues to a std::vector that is used to initialize the current Vector.
ptr
Pointer to a std::vector that is used to initialize the current Vector.
first
The first element in a sequence of objects that are used to initialize the current Vector. The type of first is passed by means of perfect forwarding. For more information, see Rvalue Reference Declarator: &&.
last
The last element in a sequence of objects that are used to initialize the current Vector. The type of last is passed by means of perfect forwarding. For more information, see Rvalue Reference Declarator: &&.
See also
Collections (C++/CX)
Platform Namespace
Creating Windows Runtime Components in C++