Why does this JavaScript work for FF and not IE8

I have just found out after half a year that an IE cannot process this script and now that my programmer is gone I'm stuck with it myself :-(

It works fine in FF

This is the code:

function updateFields(name, value) {
  var elements = getElementsByClass('field_' + name);
  for(var i=0; i<elements.length; i++) {
    var e = elements[i];
    while(e.firstChild != null) { e.removeChild(e.firstChild); }
    e.appendChild(document.createTextNode(value + ' '));*
  } // for i
} // updateFields()

My IE debugger complains about the line marked with *. It says: Error: Unexpected call to method or property access.

Can anybody spend some of his/her precious time to help? Please write answers as if I'm a four-year-old.

function getElementsByClass(cls) {
  var fields = document.getElementsByTagName('*');
  var r = new Array();

  for(var i=0; i<fields.length; i++) {
    var f = fields[i];

    var a = f.getAttribute('class');
    if(a == null)
      a = f.className;

    if(a == null)
      continue;

    var classes = a.split(' ');
    for(var j=0; j<classes.length; j++) {
      if(classes[j] == cls) {
        r.push(f);
        break;
      } // if
    } // for j
  } // for i

  return r;
}
开发者_运维技巧

Button:

<form>
  <p class="center">
    <input type="button" onclick="javascript:book_wire_transfer();" style="border: none;      border:0;"\>


  <p class="center">
    <img src="http://www.-.com/images/text/arrow_left_small.png" alt="&raquo;" class="middle" />
    <span class="submit">
      <input class="submit" type="submit" value="Book now"  />
    </span>
    <img src="http://www.-.com/images/text/arrow_right_small.png" alt="&laquo;" class="middle" />
    </p>

  </p>
  </form>

---

There are elements that IE8 and below cannot add textNodes to, though IE9 and other browsers do.

option element(use optionelement.text)
input element(use inputelement.value)
style element(use styleelement.styleSheet.cssText)
script element(use scriptelement.text)

---

getElementsByClass is not a built-in function, so it probably comes from some other library you are using that is incompatible with IE8. In this case, it is probably returning something that is not a valid set of DOM nodes.

If you could post what that method does, that would help us in debugging. Otherwise, you could try using document.querySelectorAll('.field_' + name) instead and see if that fixes it; this is supported in IE8 onwards, at least if you are in standards mode.

EDIT: your custom getElementsByClass function looks OK, although without unit tests it's hard for me to be 100% sure. One way to test would be to try and replace the body of getElementsByClass with return document.querySelectorAll('.field_' + name) and see if that fixes it... In this way, the getElementsByClass function still exists, so all your other code is not broken, but it may be more correct.

---

well, remove the * at the end of

 e.appendChild(document.createTextNode(value + ' '));*