How to escape a while loop in C#

Question

I am trying to escape a while loop. Basically, if the "if" condition is met, I would like to be able to exit this loop:

private void CheckLog() {     while (true)     {         Thread.Sleep(5000);         if (!System.IO.File.Exists("Command.bat"))             continue;          using (System.IO.StreamReader sr = System.IO.File.OpenText("Command.bat"))         {             string s = "";             while ((s = sr.ReadLine()) != null)             {                 if (s.Contains("mp4:production/CATCHUP/"))                 {                     RemoveEXELog();                      Process p = new Process();                     p.StartInfo.WorkingDirectory = "dump";                     p.StartInfo.FileName = "test.exe";                     p.StartInfo.Arguments = s;                     p.Start();                      << Escape here - if the "if" condition is met, escape the loop here >>                 }             }         }     } } 

Answer 1

Use break; to escape the first loop:

if (s.Contains("mp4:production/CATCHUP/")) {    RemoveEXELog();    Process p = new Process();    p.StartInfo.WorkingDirectory = "dump";    p.StartInfo.FileName = "test.exe";     p.StartInfo.Arguments = s;     p.Start();    break; } 

If you want to also escape the second loop, you might need to use a flag and check in the out loop's guard:

        boolean breakFlag = false;         while (!breakFlag)         {             Thread.Sleep(5000);             if (!System.IO.File.Exists("Command.bat")) continue;             using (System.IO.StreamReader sr = System.IO.File.OpenText("Command.bat"))             {                 string s = "";                 while ((s = sr.ReadLine()) != null)                 {                     if (s.Contains("mp4:production/CATCHUP/"))                     {                          RemoveEXELog();                          Process p = new Process();                         p.StartInfo.WorkingDirectory = "dump";                         p.StartInfo.FileName = "test.exe";                          p.StartInfo.Arguments = s;                          p.Start();                          breakFlag = true;                         break;                     }                 }             } 

Or, if you want to just exit the function completely from within the nested loop, put in a return; instead of a break;.

But these aren't really considered best practices. You should find some way to add the necessary Boolean logic into your while guards.

Answer 2

break or goto

while ( true ) {   if ( conditional ) {     break;   }   if ( other conditional ) {     goto EndWhile;   } } EndWhile: