how to save exception in txt file?

Question

public DataTable InsertItemDetails(FeedRetailPL objFeedRetPL) {     DataTable GetListID = new DataTable();     try     {         SqlParameter[] arParams = new SqlParameter[4];          arParams[0] = new SqlParameter("@Date", typeof(DateTime));         arParams[0].Value = objFeedRetPL.requestdate;      }     catch (Exception ex)     {         string dir = @"C:\Error.txt";  // folder location         if (!Directory.Exists(dir))         {             Directory.CreateDirectory(dir);             File.AppendAllText(Server.MapPath("~/Error.txt"), "Message :" + ex.Message + "<br/>" + Environment.NewLine + "StackTrace :" + ex.StackTrace +        "" + Environment.NewLine + "Date :" + DateTime.Now.ToString());             string New = Environment.NewLine + "-----------------------------------------------------------------------------" + Environment.NewLine;             File.AppendAllText(Server.MapPath("~/Error.txt"), New);         }     } } 

Here, I want to save an Exception in "C:\" ..I am trying In DAL... How to save the Exception In C drive Error.txt

Answer 1

Since you want to save the exception to C:\Error.txt, you don't need Directory.Exists, Directory.CreateDirectory, or Server.MapPath("~/Error.txt"). You can simply use StreamWriter like this:

string filePath = @"C:\Error.txt";  Exception ex = ...  using( StreamWriter writer = new StreamWriter( filePath, true ) ) {     writer.WriteLine( "-----------------------------------------------------------------------------" );     writer.WriteLine( "Date : " + DateTime.Now.ToString() );     writer.WriteLine();      while( ex != null )     {         writer.WriteLine( ex.GetType().FullName );         writer.WriteLine( "Message : " + ex.Message );         writer.WriteLine( "StackTrace : " + ex.StackTrace );          ex = ex.InnerException;     } } 

The above code will create C:\Error.txt if it doesn't exist, or append C:\Error.txt if it already exists.