Hide error without workaround

Question

In my code:

private void cbbMaoDeObra_TextChanged(object sender, EventArgs e)
{
    try
    {
        int resultado = Convert.ToInt32(cbbMaoDeObra.SelectedValue);
        if (resultado == 0)
        {
            btnConfirmar.Enabled = false;
        }
        else
        {
            ViewStateWorkLogger = ViewStateWorkLogger.AbleToConfirm;
        }
        MaoDeObra = resultado;
    }
    catch (Exception)
    {
        return;
    }
}

I have a try-catch to deal with some errors. My dynamic program, when started, will have a variable of type string in cbbMaoDeObra and when it starts, this string is just 'letters' and can't be parsed. SelectedValue. This is because just after some events I initialize it and read from de Database. Then, without workarounds like I did up, like using return or leave the field empty, how can I deal with these errors?

Is try { statement } catch { empty } recommended to be used?

`catch{empty}` is definitely not recommended – Sayse Jul 14 '14 at 18:29 — Sayse, Jul 14 '14 at 18:29

score 3 · Accepted Answer · edited May 23 '17 at 10:32

Generally for parsing string values, the safer option is int.TryParse. This will not raise the exception, instead it will return a bool indicating success or failure.

if(int.TryParse("123", out resultado))
{
   //parsing successful 
}
else
{
  // invalid input
}

but since SelectedValue is of type object, you can use Convert.ToIn32 and safeguard against exception (with try-catch), or convert your SelectedValue to string and then use int.TryParse.

string str = cbbMaoDeObra.SelectedValue as string;
if (str != null && int.TryParse(str, out resultado))
{
}

Is try { statement } catch { empty } recommended to be used?

There are very few places where empty catch would be useful. See: Is there any valid reason to ever ignore a caught exception. Don't use catch(Exception), catch specific exception first, log/handle it. See Best Practices for Exceptions

SelectedValue can't be parsed, as it is an object. int.TryParse will never compile this. Convert.ToInt32 will do it, but it becomes a workaround. — Marcelo Camargo, Jul 14 '14 at 18:30

Hide error without workaround

1 Answers1