Marshal.WriteInt32 Method (IntPtr, Int32, Int32)


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

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

static member WriteInt32 : 
        ptr:nativeint *
        ofs:int *
        val:int -> unit


Type: System.IntPtr

The base address in unmanaged memory to write to.

Type: System.Int32

An additional byte offset, which is added to the ptr parameter before writing.

Type: System.Int32

The value to write.

Exception Condition

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

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.

The following example demonstrates how to read and write to an unmanaged array using the ReadInt32 and WriteInt32 methods.

No code example is currently available or this language may not be supported.


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

Universal Windows Platform
Available since 8
.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
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