Error Handling

Question

In a C#.net 2010 application that I am suppose to maintain (since I am new to working with this language), I find code that looks like the following:
try
{ //do something}
catch (ex){}
In the visual studio ide, I see a a curly green under the ex.
I also do not see any using statement that I would think applies.
Thus can you tell me if this kind of code really catches any errors? if so can you explain it to me?
I put this kind of code around some of my new code and everything falls into the catch block.
Thus can you tell me what a "good" try catch block should look like aand what namespace should be included in the
using statement?

Sam Hobbs · Answer

What Usman Zafar said is good. Also look at the articles in this web site; there are many that can help also. For production programs it will help to have a methodology for showing messages to users in a manner that helps them understand problems they can fix and to report problems to you when they need your help. Note that if you say something like MessageBox.Show(Open error:  + ex.ToString()); then you will get the entire error; all the information which might be too much for non-technical users but it can help you when you are debugging and such.

Usman Zafar · Answer

It depends on what you want to do. In most cases you use something like this. try { File.Delete(path); } catch(Exception ex) { MessageBox.Show(ex.Messsage); } But sometimes it can be like this: try { File.Delete(path); } catch( FileNotFoundException ex) { MessageBox.Show(File does not exist); } catch( Exception ex) { MessageBox.Show(ex.Message); } finally { MessageBox.Show(Coming out of try catch block); }

Pravin More · Answer

Hi sie Make sure you have declared variable 'ex' like below.............. for e.g try { //do something} catch (Exception ex){} n Exception class belongs to System namespace. i.e using System Thanks pravin Mark it as Accepted Answer if its helped you.