Quick Question about what Im doing wrong

Bobby White

It is saying that input string was not in correct format, the line thats bold is the problem? Please tell me whats wrong with it, and how to fix it, thanks in advance.

{
            double a;
            double b;
            double c;

            a = double.Parse(textBox1.Text);
            b = double.Parse(textBox2.Text);

            c = Math.Sqrt((a * a) + (b * b));

            label1.Text = c.ToString();

        }

3 Replies

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ashish Jadhav16y ago
Change your code to this,
This will surely work...
    double a;
            double b;
            double c;

            a =Convert.ToDouble(textBox1.Text);
            b = Convert.ToDouble(textBox2.Text);

            c = Math.Sqrt((a * a) + (b * b));

            label1.Text = c.ToString();
Nilanka Dharmadasa16y ago
Hi bobby,

Change your code as follows.

                double a;
                double b;
                double c;

                if((double.TryParse(textBox1.Text, a)) && (double.TryParse(textBox2.Text, b))
                {
                    c = Math.Sqrt((a * a) + (b * b));
                    label1.Text = c.ToString();
                }
                else
                    MessageBox.Show("You have entered an invalid input.");

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Santhosh N16y ago
I suppose you are trying to give a value which is not either integer or double value in the second textbox and while its trying to parse the value in the textbox, it is throwing this exception...
You can only parse values which are parsable but not anything you give...