C# Signature:
[DllImport("Kernel32.dll", EntryPoint="RtlZeroMemory", SetLastError=false)]
static extern void ZeroMemory(IntPtr dest, IntPtr size);
VB Signature:
Declare Auto Sub ZeroMemory Lib "Kernel32.dll" _
Alias "RtlZeroMemory" (ByVal dest As IntPtr, ByVal size As IntPtr)
VB.NET Signature:
<DllImport("kernel32.dll")> _
Public Shared Sub ZeroMemory(ByVal addr As IntPtr, ByVal size As IntPtr)
End Sub
User-Defined Types:
None.
Alternative Managed API:
Use Marshal.Copy() to copy an zero-filled managed array onto the unmanaged heap.
Notes:
VB developers might want to check the VB declaration thoroughly...
Tips & Tricks:
Please add some!
Sample Code:
Imports System.Runtime.InteropServices
Public Class Form1
<DllImport("kernel32.dll")> _
Public Shared Sub ZeroMemory(ByVal addr As IntPtr, ByVal size As IntPtr)
End Sub
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Const elements As Integer = 50
Dim bytearray(elements) As Byte ' has elements+1 bytes
bytearray(0) = 1
bytearray(elements - 1) = 2
bytearray(elements) = 3
Debug.Print(CStr(bytearray(0)) + " " + CStr(bytearray(elements - 1)) + " " + CStr(bytearray(elements)))
Dim gch As GCHandle = GCHandle.Alloc(bytearray, GCHandleType.Pinned)
Dim abytearray As IntPtr = gch.AddrOfPinnedObject()
Dim absize As IntPtr = CType(elements, IntPtr) ' deliberately one less than size of bytearray
ZeroMemory(abytearray, absize)
gch.Free()
' show that bytearray has been filled with 0s except for the last element
Debug.Print(CStr(bytearray(0)) + " " + CStr(bytearray(elements - 1)) + " " + CStr(bytearray(elements)))
End Sub
End Class
