hi....
i am using a code like this :

double total = double.Parse(txtPF.Text) + double.Parse(txtIT.text);

where txtPF and txtIT are two text boxes on a win forrm.
if txt box doesn't contain any value it is firing exception.

i want :

try
{
double total = double.Parse(txtPF.Text) + double.Parse(txtIT.text);
}
catch(Exception exc)
{
  //some code through which i can find out exactly which text box fired the exception.so tht i can use :
  MessageBox.Show("please enter a value in "+ <name of tht txt box > +"field.");
//....
}

i've tried much bt nothing seems to work.
please help.

Neither textbox is 'firing the exception'. Each textbox is quite happily returning its Text value as a string (an empty string in one instance). Its only after that that the exception is firing.

I would use validators if I were you, one, or even two for each box (on to check if the box is empty, the other to check it is a number).

/- Sam Judson : Wrox Technical Editor -/

Try this code

double dblPF;
try
{
 dblPF = double.Parse(txtPF.Text);
}
catch(Exception ex)
{
  MessageBox.Show("please enter a value in PF field.");
}

try
{
 //Now we are sure that there is no problem in txtPF sso try to add, if it throws exception then the problem must be in txtIT.
 total = double.Parse(txtPF.Text) + double.Parse(txtIT.Text);
}
catch(Exception exc)
{
  MessageBox.Show("please enter a value in IT field.");
}



Mujahid Khaleel
Web designing, development, E-commerce applications.

Take a look at the Double.TryParse function.

--

Joe (Microsoft MVP - XML)

thanks for a quick reply...
i've used validator for a number...but not for an empty string...
your idea seems to be a good one....
thanks again...

now i think i shud've ask the question like this..:

if a statement contains more than one control's participation, and then fires an exception...then is there any way to know exactly which control's action was responsible for the exception....

thanks in advance for this one....

And the answer is, no. As I said, the exception is not firing from inside the control, therefore the stack trace would not contain the control anywhere in its history. Even then, trying to analyse the stack trace would be the wrong way to do this.

On an aside, if you expecting an action to fail then using exceptions to trap the error is not the most performant way to perform this - far better to do two TryParse operations, check if either fails, then add the two resulting numbers.

/- Sam Judson : Wrox Technical Editor -/

aha....
tht seems to be exactly the defination i was looking for....
thanks a lot....

hi....
tryParse is working perfectly....
thanks for the support....

hi....
interesting solution...and working perfectly also...
thanks for ur support....

raykaash - A forum tip: It's not necessary to quote every response when replying. We can follow the thread on the forum itself. If you want to address a specific statement in a previous post then by all means quote just that statement to provide response context.

-Peter