title: Fill a textbox based on another textbox text
body: <p>I have TextBoxA and TextBoxB. What i want to do is , whenever i put a number (yes, both of the textboxes values are always integers) in TextBoxA , TextBoxB should "autocomplete" with value (100-TextBoxA). Same thing goes for TextBoxB.  The sum of TextBoxA and TextBoxB should always be 100. </p>
  
  <p>Here's what i've already tried:</p>
  
  <pre><code>static void TextBoxA_TextChanged()...
  {
    int a = Convert.ToInt32(TextBoxA.Text);
    int b = Convert.ToInt32(TextBoxB.Text);
    string text = (100-a).ToString();
    TextBoxB.Text = text;
  }
  
  Static void TextBoxB_TextChanged()...
  {
    int a = Convert.ToInt32(TextBoxA.Text);
    int b = Convert.ToInt32(TextBoxB.Text);
    string text = (100-b).ToString();
    TextBoxA.Text = text;
  }
  </code></pre>
  
  <p>But it doesn't work.</p>