Hi, U advice are so interessant. It helps me sssssssssssso to find a solution of my problem.These is the two steps that solves my problem: 1- using of string builder concept:
StringBuilder lineBuilder = new StringBuilder ();
headLine = strEnteteHead + strNumLine;
lineBuilder .Append (headLine);
lineBuilder.Append (endOfLine);
then englobing it in my streamwriter:
monStreamWriter.WriteLine(lineBuilder.ToString());
// Fermer le streamwriter.
monStreamWriter.Close();
return monStreamWriter;
2- Doing one Response.write ( not like I do in the begining) when reading my file with streamreader
StreamReader report = (StreamReader)GGetValue ("_Report");
this.Response.Write (report.ReadToEnd().ToString ());
Now, orpning my file with all (word , wordPad, EXCEL,...),lines are sssssso clear Thank u for u help :laugh: