title: Javascript IndexOf with integers in string not working
body: <p>Can anyone tell me why does this not work for integers but works for characters? I really hate reg expressions since they are cryptic but will if I have too. Also I want to include the "-()" as well in the valid characters.</p>
  
  <pre><code>String.prototype.Contains = function (str) {  
      return this.indexOf(str) != -1;
  };
  
  var validChars = '0123456789';               
  
  var str = $("#textbox1").val().toString();
  if (str.Contains(validChars)) {
      alert("found");
  } else {
      alert("not found");
  }
  </code></pre>