using System;

 namespace GenericHid

 {

 	/// <summary>

 	/// Used only in Debug.Write statements.

 	/// </summary>

 	/// 

 	internal sealed partial class Debugging

     {         

         ///  <summary>

         ///  Get text that describes the result of an API call.

         ///  </summary>

         ///  

         ///  <param name="functionName"> the name of the API function. </param>

         ///  

         ///  <returns>

         ///  The text.

         ///  </returns>

         internal String ResultOfApiCall( String functionName ) 

         {

 	        var resultString = new String(Convert.ToChar( 0 ), 129 ); 

             // Returns the result code for the last API call.

             Int32 resultCode = System.Runtime.InteropServices.Marshal.GetLastWin32Error(); 

             // Get the result message that corresponds to the code.

             Int64 temp = 0;

 			Int32 bytes = NativeMethods.FormatMessage(NativeMethods.FormatMessageFromSystem, ref temp, resultCode, 0, resultString, 128, 0); 

             // Subtract two characters from the message to strip the CR and LF.

             if ( bytes > 2 ) 

             { 

                 resultString = resultString.Remove( bytes - 2, 2 ); 

             }             

             // Create the String to return.

             resultString = Environment.NewLine + functionName + Environment.NewLine + "Result = " + resultString + Environment.NewLine; 

             return resultString;             

         }         

     }  

 }