// File: messagebox.w_js
   Window.AppendMenu(0,"MF_STRING",8000,"&Show the message box");
   Window.DrawMenuBar();

function WM_COMMAND(id) {

if (id != 8000) return;

var title = "The Caption for message box";
var message = "The message for you";
var mask = 64;

// The meaning of mask is the same as in the Microsoft 
// Win32R application programming interface MessageBox 
// function. The following tables show the values and 
// their meanings. You can combine values in these tables.

   // Button Types
   // 0 Show OK button. 
   // 1 Show OK and Cancel buttons. 
   // 2 Show Abort, Retry, and Ignore buttons. 
   // 3 Show Yes, No, and Cancel buttons. 
   // 4 Show Yes and No buttons. 
   // 5 Show Retry and Cancel buttons. 

   // Icon Types
   // 16 Show "Stop Mark" icon. 
   // 32 Show "Question Mark" icon. 
   // 48 Show "Exclamation Mark" icon. 
   // 64 Show "Information Mark" icon. 

var i = Window.MessageBox(title, message, mask);
    // 1 OK button 
    // 2 Cancel button 
    // 3 Abort button 
    // 4 Retry button 
    // 5 Ignore button 
    // 6 Yes button 
    // 7 No button 

Window.TextOut(0,50,50,"The return value: " + i); 
Window.UpdateWindow();
}