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Type.IsValueType Property

  • Reference

Definition

Namespace:
System
Assembly:
System.Runtime.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll
Source:
Type.cs
Source:
Type.cs
Source:
Type.cs

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

public:
 property bool IsValueType { bool get(); };
public bool IsValueType { get; }
member this.IsValueType : bool
Public ReadOnly Property IsValueType As Boolean

Property Value

Boolean

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

Implements

IsValueType

Examples

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

using namespace System;

// Declare an enum type.
public enum class NumEnum
{
   One, Two
};

int main()
{
    bool flag = false;
    NumEnum testEnum = NumEnum::One;
      
    // Get the type of testEnum.
    Type^ t = testEnum.GetType();
      
    // Get the IsValueType property of the testEnum
    // variable.
    flag = t->IsValueType;
    Console::WriteLine("{0} is a value type: {1}", t->FullName, flag);
}

using System;

// Declare an enum type.
enum NumEnum { One, Two }

public class Example
{

    public static void Main(string []args)
    {
        bool flag = false;
        NumEnum testEnum = NumEnum.One;
        // Get the type of testEnum.
        Type t = testEnum.GetType();
        // Get the IsValueType property of the testEnum variable.
        flag = t.IsValueType;
        Console.WriteLine("{0} is a value type: {1}", t.FullName, flag);
    }
}
// The example displays the following output:
//        NumEnum is a value type: True

// Declare an enum type.
type NumEnum = One = 1 | Two = 2

let testEnum = NumEnum.One
// Get the type of testEnum.
let t = testEnum.GetType()
// Get the IsValueType property of the testEnum variable.
let flag = t.IsValueType
printfn $"{t.FullName} is a value type: {flag}"
// The example displays the following output:
//        NumEnum is a value type: True

' Declare an enum type.
Enum NumEnum
    One
    Two
End Enum
    
Public Class Example

    Public Shared Sub Main()
        Dim flag As Boolean = False
        Dim testEnum As NumEnum = NumEnum.One
        ' Get the type of myTestEnum.
        Dim t As Type = testEnum.GetType()
        ' Get the IsValueType property of the myTestEnum variable.
         flag = t.IsValueType()
         Console.WriteLine("{0} is a value type: {1}", t.FullName, flag)
     End Sub 
 End Class  
' The example displays the following output:
'       NumEnum is a value type: True

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's 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.

Applies to

See also