How can I check if a string is a number?

Question

I\'d like to know on C# how to check if a string is a number (and just a number).

Example :

141241   Yes
232a23   No
12412a   No

an

Answer 1

Try This

here i perform addition of no and concatenation of string

 private void button1_Click(object sender, EventArgs e)
        {
            bool chk,chk1;
            int chkq;
            chk = int.TryParse(textBox1.Text, out chkq);
            chk1 = int.TryParse(textBox2.Text, out chkq);
            if (chk1 && chk)
            {
                double a = Convert.ToDouble(textBox1.Text);
                double b = Convert.ToDouble(textBox2.Text);
                double c = a + b;
                textBox3.Text = Convert.ToString(c);
            }
            else
            {
                string f, d,s;
                f = textBox1.Text;
                d = textBox2.Text;
                s = f + d;
                textBox3.Text = s;
            }
        }