function isValidEmail(formName, elementName){
	var emailRegEx = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	var obj = document.forms[formName].elements[elementName];
	var str = obj.value;
	if(str.match(emailRegEx)) 
	{
		obj.style.backgroundColor = "#ffffff";
		return true;
	}
	obj.style.backgroundColor = "#FFFF99";
	obj.focus();
	return false;
}

function isNotNull(formName, elementName){
	var obj = document.forms[formName].elements[elementName];
	var str = obj.value==null?"":obj.value;
	var retVal;
	if(str.length>0) retVal=true;
	else retVal= false;
	
	if(retVal) 
	{
		obj.style.backgroundColor = "#ffffff";
	}else{
		obj.style.backgroundColor = "#FFFF99";
		obj.focus();
	}
	return retVal;
}

function trim(str, chars) {
	return ltrim(rtrim(str, chars), chars);
}
 
function ltrim(str, chars) {
	chars = chars || "\\s";
	return str.replace(new RegExp("^[" + chars + "]+", "g"), "");
}
 
function rtrim(str, chars) {
	chars = chars || "\\s";
	return str.replace(new RegExp("[" + chars + "]+$", "g"), "");
}