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Type.IsValueType Property

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Gets a value indicating whether the Type is a value type.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public ReadOnly Property IsValueType As Boolean

public bool IsValueType { get; }

Property Value

Type: System.Boolean
true if the Type is a value type; otherwise, false.

Remarks

Value types are types that are represented as sequences of bits; value types are not classes or interfaces. Value types are referred to as "structs" in some programming languages. Enums are a special case of value types.

This property returns false for the ValueType class, because ValueType is not a value type itself. It is the base class for all value types, and therefore any value type can be assigned to it. This would not be possible if ValueType itself was a value type. Value types are boxed when they are assigned to a field of type ValueType.

This property returns true for enumerations, but not for the Enum type itself. For an example that demonstrates this behavior, see IsEnum.

This property is read-only.

Examples

The following example creates a variable of type MyEnum, checks for the IsValueType property, and displays the result.

NoteNote:

To run this example, see Building Examples That Use a Demo Method and a TextBlock Control.

 
Public Class Example

    ' Declare an enum type.
    Enum MyEnum
        One
        Two
    End Enum 'MyEnum

    Public Overloads Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)

        Dim myBool As Boolean = False
        Dim myTestEnum As MyEnum = MyEnum.One
        ' Get the type of myTestEnum.
        Dim myType As Type = myTestEnum.GetType()
        ' Get the IsValueType property of the myTestEnum variable.
        myBool = myType.IsValueType
        outputBlock.Text += String.Format("Is {0} a value type? {1}." & vbLf, _
            myType.FullName, myBool)
    End Sub 
End Class 

using System;

public class Example
{
    // Declare an enum type.
    enum MyEnum
    {
        One,
        Two
    }
    public static void Demo(System.Windows.Controls.TextBlock outputBlock)
    {
        bool myBool = false;
        MyEnum myTestEnum = MyEnum.One;
        // Get the type of myTestEnum.
        Type myType = myTestEnum.GetType();
        // Get the IsValueType property of the myTestEnum 
        // variable.
        myBool = myType.IsValueType;
        outputBlock.Text += String.Format("Is {0} a value type? {1}.\n", 
            myType.FullName, myBool.ToString());
    }
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

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