C# Signature:

[DllImport("kernel32.dll")]
static extern bool WriteProcessMemory(IntPtr hProcess, IntPtr lpBaseAddress,
   byte [] lpBuffer, UIntPtr nSize, out IntPtr lpNumberOfBytesWritten);

VB.Net Signature:

<DllImport("kernel32.dll")> _
Public Shared Function WriteProcessMemory(ByVal hProcess As IntPtr, ByVal lpBaseAddress As IntPtr, ByVal lpBuffer As Byte(), ByVal nSize As UIntPtr, <Out()> ByRef lpNumberOfBytesWritten As IntPtr) As Boolean
End Function

User-Defined Types:

None.

Notes:

None.

Tips & Tricks:

Please add some!

Sample Code:

public IntPtr WriteByteArray( IntPtr BaseAddress, byte [] NewVal )
{
    // Return Value
    int ReturnVal;

    // Write Memory Byte Array
    ReturnVal = WriteProcessMemory( this.hProcess, BaseAddress, NewVal, (UIntPtr)NewVal.Length, out this.BytesWritten );

    return this.BytesWritten;
}

'VB.Net
Public Shared Function Poke(ByVal proc As Process, ByVal target As Integer, ByVal data As Byte()) As Boolean
    Return WriteProcessMemory(proc.Handle, New IntPtr(target), data, New UIntPtr(CType(data.Length, UInt32)), New IntPtr(0))
End Function

Alternative Managed API:

The ManagedWindowsApi project (http://mwinapi.sourceforge.net) provides a ProcessMemoryChunk class to allocate and access memory of a different process.

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