function getWidth() {
  var width = 0;
  if( typeof( window.innerWidth ) == 'number' ) {
    width = window.innerWidth;
  } else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
    width = document.documentElement.clientWidth;
  } else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
    width = document.body.clientWidth;
  }
  return width;
}
function getHeight() {
  var height = 0;
  if( typeof( window.innerHeight ) == 'number' ) {
    height = window.innerHeight;
  } else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
    height = document.documentElement.clientHeight;
  } else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
    height = document.body.clientHeight;
  }
  return height;
}
function Dialog (sUrl, iWidth, iHeight)
{
    var posX = (screen.width / 2) - (iWidth/2);
    var posY = (screen.height / 2) - (iHeight/2);

    dialog = window.open (sUrl, "dialog", "width="+iWidth+", height="+iHeight+", resizable=no, scrollbars=yes");

    dialog.moveTo (posX, posY);
    dialog.focus ();
}