C# Signature:

[DllImport("kernel32.dll", SetLastError=true)]
static extern Int32 ReadProcessMemory(IntPtr hProcess, IntPtr lpBaseAddress,[Out] byte[] buffer, UInt32 size, out IntPtr lpNumberOfBytesRead);

VB Signature:

   Private Declare Function ReadProcessMemory Lib "kernel32" (ByVal hProcess As Integer, ByVal lpBaseAddress As Integer, ByVal lpBuffer As Integer, ByVal nSize As Integer, ByRef lpNumberOfBytesRead As Integer) As Integer

User-Defined Types: