// validaciones para formularios

function isEmpty(s) {   

	return ((s == null) || (s.length == 0));

}



function isWhitespace(s) {

	var reWhitespace = /^\s+$/gi;

	return (isEmpty(s) || reWhitespace.test(s));

}



function isEmail(strEmail) 

{

	return ( strEmail.search( new RegExp("^([a-zA-Z0-9_\\-\\.]+)@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.)|(([a-zA-Z0-9\\-]+\\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\\]?)$","gi") ) != -1 );

}