detect_mouse_cursor.js

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addLoadListener(init);

function init()
{
  attachEventListener(document, "mousemove", displayCursorPosition, false);

  return true;
}

function displayCursorPosition(event)
{
  if (typeof event == "undefined")
  {
    event = window.event;
  }

  var scrollingPosition = getScrollingPosition();
  var cursorPosition = [0, 0];

  if (typeof event.pageX != "undefined" && typeof event.x != "undefined")
  {
    cursorPosition[0] = event.pageX;
    cursorPosition[1] = event.pageY;
  }
  else
  {
    cursorPosition[0] = event.clientX + scrollingPosition[0];
    cursorPosition[1] = event.clientY + scrollingPosition[1];
  }

  var paragraph = document.getElementsByTagName("p")[0];

  paragraph.replaceChild(document.createTextNode("Your mouse is currently located at: " + cursorPosition[0] + "," + cursorPosition[1]), paragraph.firstChild);

  return true;
}

function addLoadListener(fn)
{
  if (typeof window.addEventListener != 'undefined')
  {
    window.addEventListener('load', fn, false);
  }
  else if (typeof document.addEventListener != 'undefined')
  {
    document.addEventListener('load', fn, false);
  }
  else if (typeof window.attachEvent != 'undefined')
  {
    window.attachEvent('onload', fn);
  }
  else
  {
    var oldfn = window.onload;
    if (typeof window.onload != 'function')
    {
      window.onload = fn;
    }
    else
    {
      window.onload = function()
      {
        oldfn();
        fn();
      };
    }
  }
}

function attachEventListener(target, eventType, functionRef, capture)
{
  if (typeof target.addEventListener != "undefined")
  {
    target.addEventListener(eventType, functionRef, capture);
  }
  else if (typeof target.attachEvent != "undefined")
  {
    target.attachEvent("on" + eventType, functionRef);
  }
  else
  {
    eventType = "on" + eventType;

    if (typeof target[eventType] == "function")
    {
      var oldListener = target[eventType];

      target[eventType] = function()
      {
        oldListener();

        return functionRef();
      }
    }
    else
    {
      target[eventType] = functionRef;
    }
  }

  return true;
}

function getScrollingPosition()
{
  //array for X and Y scroll position
  var position = [0, 0];

  //if the window.pageYOffset property is supported
  if(typeof window.pageYOffset != 'undefined')
  {
    //store position values
    position = [
        window.pageXOffset,
        window.pageYOffset
    ];
  }

  //if the documentElement.scrollTop property is supported
  //and the value is greater than zero
  if(typeof document.documentElement.scrollTop != 'undefined'
    && document.documentElement.scrollTop > 0)
  {
    //store position values
    position = [
        document.documentElement.scrollLeft,
        document.documentElement.scrollTop
    ];
  }

  //if the body.scrollTop property is supported
  else if(typeof document.body.scrollTop != 'undefined')
  {
    //store position values
    position = [
        document.body.scrollLeft,
        document.body.scrollTop
    ];
  }

  //return the array
  return position;
}