function isEmail(emailStr) {
	var emailPat=/^(.+)@(.+)$/;
	var matchArray=emailStr.match(emailPat);
	if (matchArray==null) {
		return false;
	}
		return true;
}

function validateEmail(email) {
    if (email.length <= 0) {		
		return false;
	} else {
		var splitted = email.match("^(.+)@(.+)$");
		if (splitted == null) {
		    return false;
		}
		if (splitted[1] != null ) {
		    var regexp_user=/^\"?[\w-_\.]*\"?$/;
		    if(splitted[1].match(regexp_user) == null) return false;
		}
		if (splitted[2] != null)	{
			var regexp_domain=/^[\w-\.]*\.[A-Za-z]{2,4}$/;
			if (splitted[2].match(regexp_domain) == null) {
				var regexp_ip =/^\[\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\]$/;
				if (splitted[2].match(regexp_ip) == null) {
				    return false;
				}
			}
			return true;
		}
		return false;
	}
}

function isAvailibleLength(str, borderLow, borderHigh) {
	if(str.length < borderLow) { 
		return false;
	}
	if(str.length > borderHigh) {
		return false;
	}
	return true;
}

function isAvailibleMobileNumber(mobileNumber) {
    if (mobileNumber.substring(0,1) == "("  && mobileNumber.substring(4,5) == ")" && mobileNumber.substring(8,9) == "-" 
        && isDigit(mobileNumber.substring(1,4)) && isDigit(mobileNumber.substring(5,8))
        && isDigit(mobileNumber.substring(9,13))) {
        return true;
    }
    return false;
}

function isDigit(s)
{
	var patrn=/^[0-9]{1,20}$/;

	if (!patrn.exec(s)) {
		return false;
	}

	return true;
}

// do trim
function trim(str){
	return str.replace(/(^[\s]*)|([\s]*$)/g, "");
}

//check the field is empty
function checkIsEmpty(str) {
    if(trim(str) == "") 
        return true;
    else
        return false;
}