title: formatexception was unhandled (double.parse)
body: <p>I'm having some problem with my application. when i click ok or cancel in the messagebox. it happens. Here is my code. it says that the string of <strong>foot</strong> is not write. It says input string is not in formate. What should i do.
  <a href="http://i.stack.imgur.com/rMixi.png" rel="nofollow">This is a screenshot</a></p>
  
  <pre><code>private void button1_Click(object sender, EventArgs e)
      {
         if ((textBox1.Text == "") || (textBox2.Text == "") || (textBox3.Text == "") || (textBox4.Text == ""))
          {
              MessageBox.Show("Please Fill All The Informations", "Error", MessageBoxButtons.OKCancel, MessageBoxIcon.Warning);
          };
  
  
  
          double foot, inches;
          double height;
          double weight;
          double age;
          double BMRM;
          double BMRF;
          double BMI;
  
          foot = double.Parse(textBox2.Text); 
          inches = double.Parse(textBox1.Text);
          height = 30.48 * (foot + (0.083 * inches));
          weight = double.Parse(textBox3.Text);
          age = double.Parse(textBox4.Text);
          BMRM = 66 + (13.7 * weight) + (5 * height) - (6.8 * age);
          BMRF = 655 + (9.6 * weight) + (1.8 * height) - (4.7 * age);
          BMI = (weight / ((height * height) / 10000));
  
          if (radioButton1.Checked)
          {
              textBox5.Text = BMRM.ToString();
          };
          if (radioButton2.Checked)
          {
              textBox5.Text = BMRF.ToString();
          };
          textBox6.Text = BMI.ToString();
  
          if (BMI &lt;= 18.5)
          {
              textBox7.Text = "Your weight is low. You have to eat properly.";
          };
          if (BMI &gt; 18.5 &amp;&amp; BMI &lt;= 24.9)
          {
              textBox7.Text = "You are Healthy";
          };
          if (BMI &gt; 25 &amp;&amp; BMI &lt;= 29.9)
          {
              textBox7.Text = "You have gained a little fat";
          };
  
          if (BMI &gt; 30 &amp;&amp; BMI &lt;= 34.9)
          {
              textBox7.Text = "You are in the fist step of Fat.You have take exercise regularly";
          };
          if (BMI &gt; 35 &amp;&amp; BMI &lt; 40)
          {
              textBox7.Text = "You are in the second step of Fat. You need to exercise regularly";
          }
          if (BMI &gt; 40)
          {
              textBox7.Text = "You have gained a lot of fat. It can cause you death. Please take Doctor's advise";
          };
  </code></pre>