SizeOf Method (Type)
Collapse the table of content
Expand the table of content

Marshal.SizeOf Method (Type)


Returns the size of an unmanaged type in bytes.

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

public static int SizeOf(
	Type t


Type: System.Type

The type whose size is to be returned.

Return Value

Type: System.Int32

The size of the specified type in unmanaged code.

Exception Condition

The t parameter is a generic type.


The t parameter is null.

You can use this method when you do not have a structure. The layout must be sequential or explicit.

The size returned is the size of the unmanaged type. The unmanaged and managed sizes of an object can differ. For character types, the size is affected by the CharSet value applied to that class.

The following example demonstrates calling the SizeOf method. This code example is part of a larger example provided for the Marshal class.

// Demonstrate the use of the SizeOf method of the Marshal class.
Console.WriteLine("Number of bytes needed by a Point object: {0}", 
Point p = new Point();
Console.WriteLine("Number of bytes needed by a Point object: {0}",

Universal Windows Platform
Available since 4.5
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Return to top
© 2015 Microsoft