function trim(strText) 
{ 
    // this will get rid of leading spaces 
    while ( strText.substring( 0, 1 ) == ' ' ) 
        strText = strText.substring( 1, strText.length );

    // this will get rid of trailing spaces 
    while ( strText.substring( strText.length-1, strText.length ) == ' ' )
        strText = strText.substring( 0, strText.length-1 );

   return strText;
}

function validateImage(url){
  var img = new Image();
  img.src = url;
  return img.height>0;
}