Question

I want to write some try and catch that catch any type or exception, is this code is enough (that’s the way to do in Java)?

try {
code....
}
catch (Exception ex){}

Or should it be

try {
code....
}
catch {}

?

Answer 1

Both approaches will catch all exceptions. There is no significant difference between your two code examples except that the first will generate a compiler warning because ex is declared but not used.

But note that some exceptions are special and will be rethrown automatically.

ThreadAbortException is a special exception that can be caught, but it will automatically be raised again at the end of the catch block.

http://msdn.microsoft.com/en-us/library/system.threading.threadabortexception.aspx

---

As mentioned in the comments, it is usually a very bad idea to catch and ignore all exceptions. Usually you want to do one of the following instead:

• Catch and ignore a specific exception that you know is not fatal.

  catch (SomeSpecificException)
  {
      // Ignore this exception.
  }
  

• Catch and log all exceptions.

  catch (Exception e)
  {
      // Something unexpected went wrong.
      Log(e);
      // Maybe it is also necessary to terminate / restart the application.
  }
  

• Catch all exceptions, do some cleanup, then rethrow the exception.

  catch
  {
      SomeCleanUp();
      throw;
  }
  

Note that in the last case the exception is rethrown using throw; and not throw ex;.