Sends a string to the debugger for display.

C# Signature:

[DllImport("kernel32.dll")]
static extern void OutputDebugString(string lpOutputString);

VB.NET Signature:

<DllImport("kernel32.dll")> _
Shared Sub OutputDebugString(ByVal lpOutputString As String)
End Sub

Or (as in VB 6)

Public Declare Sub OutputDebugString Lib "kernel32" Alias _
    "OutputDebugStringA" (ByVal lpOutputString As String)

User-Defined Types:

None.

Notes:

None.

Tips & Tricks:

Get DebugView here (http://www.sysinternals.com/Utilities/DebugView.html) to display the output of OutputDebugString.

This C# example extends the OutputDebugString(...) with variable arguments:

        public static void OutputDebugStringVarArg(
        string format,
        params object[] args)
        {
        try
        {
            OutputDebugString(string.Format(format, args));
        }
        catch (Exception)
        {
            return;
        }
        }

Now run the function as follows: OutputDebugStringVarArg("It is {0} past {1}", new object[] {5,10 });

Get OutputDebugString function implementation that accepts variable number of arguments like printf here (http://www.go4expert.com/forums/showthread.php?t=871)

Sample Code:

1. Create a new C# windows console application project.

2. Add the following

using System.Runtime.InteropServices;

below

using System.Text;

3. Add the following as the first statement of the main function.

OutputDebugString("OutputDebugString Successfully executed");

Now execute the program with DebugView Open

Alternative Managed API:

System.Diagnostics.Debug.WriteLine

System.Diagnostics.Debugger.Log

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