Why am I getting a FormatException was unhandled error?

Question

I have created a program, and a extensive test of it, I\'m getting a error that says \"FormatException was unhandled, Input string was not in a correct format\". The problem

Answer 1

The problem occurs when I leave either of the text boxes blank

That's the issue. You are using int.Parse on an empty string. An empty string is not a valid integer representation and the parse fails.

You can test for the value in the textbox and default to something reasonable instead:

int minsEntered = 0;
int secsEntered = 0;

if(!string.IsNullOrWhitespace(textMins.Text))
{
  minsEntered = int.Parse(txtMins.Text);
}

if(!string.IsNullOrWhitespace(txtSecs.Text))
{
  secsEntered = int.Parse(txtSecs.Text);
}