Question

In Asp.net using c# ,I am having

int sum = Convert.ToInt32(txtbox1.Text) + Convert.ToInt32(txtbox2.Text);

When i have an empty textbox, i get the error “Input string is not in a correct format”.

So, I am wondering if there is a simple way to add textbox values only they are integers, if not take the textbox value as 0.

Thanks in advance!

Answer 1

You can either set the default value of the TextBox to 0, or use TryParse:

int val1, val2;
Int.TryParse(txtbox1.Text,out val1));
Int.TryParse(txtbox2.Text,out val2));
int sum =  val1 + val2;

Note that you do not need to set the values to 0 if the parse fails since they will be 0 anyways. If you want to be explicit, however:

int val1, val2;
if(!Int.TryParse(txtbox1.Text,out val1))) val1 = 0;
if(!Int.TryParse(txtbox2.Text,out val2))) val2 = 0;
int sum =  val1 + val2;