IReference<T> Interface
Definition
Important
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Enables arbitrary enumerations, structures, and delegate types to be used as property values.
.NET This interface appears as Nullable<T>.
C++/CX This interface appears as Platform::IBox<T>
public interface class IReference : IPropertyValue/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.FoundationContract, 65536)]
/// [Windows.Foundation.Metadata.Guid(1640068870, 11621, 4576, 154, 232, 212, 133, 100, 1, 84, 114)]
template <typename T>
struct IReference : IPropertyValue[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.FoundationContract), 65536)]
[Windows.Foundation.Metadata.Guid(1640068870, 11621, 4576, 154, 232, 212, 133, 100, 1, 84, 114)]
public interface Nullable<T> : IPropertyValuePublic Interface Nullable(Of T)
Implements IPropertyValueType Parameters
- T
- Attributes
- Implements
Windows requirements
| Device family |
Windows 10 (introduced in 10.0.10240.0)
|
| API contract |
Windows.Foundation.FoundationContract (introduced in v1.0)
|
Examples
bool flag = myScrollViewer.ChangeView(2d, null, null);
bool flag{ myScrollViewer.ChangeView(Windows::Foundation::IReference<double>{2.f}, nullptr, nullptr) };
Remarks
When programming with .NET, this interface is hidden, and you should use the Nullable<T> class. All Windows Runtime members where the basic IDL signature shows IReference (with a constraint) are, instead, exposed using the syntax of the nullable value type (for example, bool? in C#).
When programming with C++/CX, this interface is hidden, and you should use the Platform::IBox<T> interface. All Windows Runtime members where the basic IDL signature shows IReference (with a constraint) are instead exposed using Platform::IBox<T> with the template as a particular value type. This is how C++/CX implements nullable value types. For more info, see Value classes and structs (C++/CX).
Because both .NET and C++/CX have projection equivalents, don't implement this interface unless you are using WRL and/or writing code for a Windows Runtime component, and need a nullable value type.
Interface inheritance
IReference<T> inherits IPropertyValue. Types that implement IReference<T> also implement the interface members of IPropertyValue.
Properties
| IsNumericScalar |
Gets a value that indicates whether the property value is a scalar value. (Inherited from IPropertyValue) |
| Type |
Returns the type stored in the property value. (Inherited from IPropertyValue) |
| Value |
Gets the type that is represented as an IPropertyValue. |
Methods
| GetBoolean() |
Returns the Boolean value stored as a property value. (Inherited from IPropertyValue) |
| GetBooleanArray(Boolean[]) |
Returns the array of Boolean values stored as a property value. (Inherited from IPropertyValue) |
| GetChar16() |
Returns the Unicode character stored as a property value. (Inherited from IPropertyValue) |
| GetChar16Array(Char[]) |
Returns the array of Unicode characters stored as a property value. (Inherited from IPropertyValue) |
| GetDateTime() |
Returns the date and time value stored as a property value. (Inherited from IPropertyValue) |
| GetDateTimeArray(DateTime[]) |
Returns the array of date and time values stored as a property value. (Inherited from IPropertyValue) |
| GetDouble() |
Returns the floating-point value stored as a property value. (Inherited from IPropertyValue) |
| GetDoubleArray(Double[]) |
Returns the array of floating-point values stored as a property value. (Inherited from IPropertyValue) |
| GetGuid() |
Returns the GUID value stored as a property value. (Inherited from IPropertyValue) |
| GetGuidArray(Guid[]) |
Returns the array of GUID values stored as a property value. (Inherited from IPropertyValue) |
| GetInspectableArray(Object[]) |
Returns the array of inspectable objects stored as a property value. (Inherited from IPropertyValue) |
| GetInt16() |
Returns the integer value stored as a property value. (Inherited from IPropertyValue) |
| GetInt16Array(Int16[]) |
Returns the array of integer values stored as a property value. (Inherited from IPropertyValue) |
| GetInt32() |
Returns the integer value stored as a property value. (Inherited from IPropertyValue) |
| GetInt32Array(Int32[]) |
Returns the array of integer values stored as a property value. (Inherited from IPropertyValue) |
| GetInt64() |
Returns the integer value stored as a property value. (Inherited from IPropertyValue) |
| GetInt64Array(Int64[]) |
Returns the array of integer values stored as a property value. (Inherited from IPropertyValue) |
| GetPoint() |
Returns the point structure stored as a property value. (Inherited from IPropertyValue) |
| GetPointArray(Point[]) |
Returns the array of point structures stored as a property value. (Inherited from IPropertyValue) |
| GetRect() |
Returns the rectangle structure stored as a property value. (Inherited from IPropertyValue) |
| GetRectArray(Rect[]) |
Returns the array of rectangle structures stored as a property value. (Inherited from IPropertyValue) |
| GetSingle() |
Returns the floating-point value stored as a property value. (Inherited from IPropertyValue) |
| GetSingleArray(Single[]) |
Returns the array of floating-point values stored as a property value. (Inherited from IPropertyValue) |
| GetSize() |
Returns the size structure stored as a property value. (Inherited from IPropertyValue) |
| GetSizeArray(Size[]) |
Returns the array of size structures stored as a property value. (Inherited from IPropertyValue) |
| GetString() |
Returns the string value stored as a property value. (Inherited from IPropertyValue) |
| GetStringArray(String[]) |
Returns the array of string values stored as a property value. (Inherited from IPropertyValue) |
| GetTimeSpan() |
Returns the time interval value stored as a property value. (Inherited from IPropertyValue) |
| GetTimeSpanArray(TimeSpan[]) |
Returns the array of time interval values stored as a property value. (Inherited from IPropertyValue) |
| GetUInt16() |
Returns the unsigned integer value stored as a property value. (Inherited from IPropertyValue) |
| GetUInt16Array(UInt16[]) |
Returns the array of unsigned integer values stored as a property value. (Inherited from IPropertyValue) |
| GetUInt32() |
Returns the unsigned integer value stored as a property value. (Inherited from IPropertyValue) |
| GetUInt32Array(UInt32[]) |
Returns the array of unsigned integer values stored as a property value. (Inherited from IPropertyValue) |
| GetUInt64() |
Returns the unsigned integer value stored as a property value. (Inherited from IPropertyValue) |
| GetUInt64Array(UInt64[]) |
Returns the array of unsigned integer values stored as a property value. (Inherited from IPropertyValue) |
| GetUInt8() |
Returns the byte value stored as a property value. (Inherited from IPropertyValue) |
| GetUInt8Array(Byte[]) |
Returns the array of byte values stored as a property value. (Inherited from IPropertyValue) |