function isEmail(elem, helperMsg){
	var emailExp = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;
		if(elem.value.match(emailExp)){
			return true;
		}else{
			alert(helperMsg);
			elem.focus();
			return false;
		}
	}


function isAlphanumeric(elem, helperMsg){
	var alphaExp = /^[0-9a-zA-Z]+$/;
		if(elem.value == ""){
			return true;
			}
		else if(elem.value.match(alphaExp)){
			return true;
		}else{
			alert(helperMsg);
			elem.focus();
			return false;
		}
	}


function isPDF(elem, helperMsg){
	var alphaExp = /^[\w\-\.\+a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{3,3}$/;
		if(elem.value == ""){
			return true;
			}
		else if(elem.value.match(alphaExp)){
			return true;
		}else{
			alert(helperMsg);
			elem.focus();
			return false;
		}
	}