WriteInt32 Method (Object, Int32, Int32)

Marshal.WriteInt32 Method (Object, Int32, Int32)

Writes a 32-bit signed integer value to unmanaged memory at a specified offset.

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

public static void WriteInt32(
	Object ptr,
	int ofs,
	int val


Type: System.Object
The base address in unmanaged memory of the target object.
Type: System.Int32
An additional byte offset, which is added to the ptr parameter before writing.
Type: System.Int32
The value to write.


Base address (ptr) plus offset byte (ofs) produces a null or invalid address.


ptr is an ArrayWithOffset object. This method does not accept ArrayWithOffset parameters.

WriteInt32 enables direct interaction with an unmanaged 32-bit signed array, eliminating the expense of copying an entire unmanaged array (using Marshal.Copy) to a separate managed array before setting its element values.

Writing to unaligned memory locations is supported.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

  • SecurityCriticalAttribute 

    requires full trust for the immediate caller. This member cannot be used by partially trusted or transparent code.

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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