function checkemail(fieldname,strng)
{
 var reg2str = "\^.+\\@(\\[?)[a-z0-9\\-\\.]+\\.([a-z]{2,3}|[0-9]{1,3})(\\]?)\$";
    var reg2 = new RegExp(reg2str);
    if (!reg2.test(strng)) 
      return("\n Please enter a valid email address.");
	 else 
	 	return("");
}
function checknum(fieldname,strng)
{
	if(strng=="")
		return("\n"+fieldname+" field must not be blank");
	if(isNaN(strng))
		return("\n "+fieldname+" field contain invalid value");		
	else
		return("");
}

function checkhtml(fieldname,strng)
{
	var reg2str="<\/[a-z]+>|<[a-z]+>";
	var reg2=new RegExp(reg2str);
	if(reg2.test(strng))
		return("\n "+fieldname+" contains illegal characters.");
	else
		return "";
}

function checkpassword(fieldname,strng) {
 if (strng == "") 
    return("\n"+fieldname+" field must not be blank");
 var illegalChars = /[\W_]/; // allow only letters and numbers
    if ((strng.length < 5) || (strng.length > 15)) 
       return("\n The "+fieldname+"\'s length must lie in (5-15)");
    else if (illegalChars.test(strng)) 
      return("\n "+fieldname+" contains illegal characters.");
  	else
		return("");
}
function checkchar(fieldname,strng)
{
	if(strng=="")
	return("\n"+fieldname+" field must not be blank");
	var validchars=/^([a-zA-Z]+)+$/;
	if(validchars.test(strng))
	return("");
	else
	return("\n "+fieldname+" contains illegal characters.");
}
function checkstring(fieldname,strng)
{
	if(strng=="")
	return("\n"+fieldname+" field must not be blank");
	var validchars=/^([a-zA-Z. ]+)*$/;
	if(validchars.test(strng))
	return("");
	else
	return("\n "+fieldname+" contains illegal characters.");
}
function checkdigit(fieldname,strng)
{
		if(strng=="")
			return("\n"+fieldname+" field must not be blank");
		var valid=/^([0-9])+$/;
		if(!valid.test(strng))
			return("\n"+fieldname+" contains illegal characters.");
		else
			return("");
}
function checkphone(fieldname,strng)
{
	if(strng!="")
	{
		var stripped = strng.replace(/[\(\)\.\-\ ]/g, '');
			if (isNaN(parseInt(stripped))) 
  	 return("\n The "+fieldname+" contains illegal characters.");
 		else
 			return("");
	}
	else
	return("");
}	

function checkblank(fieldname,strng)
{
	if(strng=="")
	return("\n"+fieldname+" field must not be blank");
	else
	return("");
}

function checkurl(fieldname,strng)
{ 
if(strng!="")
{
var valid=/^http(s?):\/\/[a-z0-9|\.|-]+\.+[a-z]{2,3}/;
if(valid.test(strng))
return ("");
else
return("\n Please enter valid website url");
}
else
return ("");
}

function trim(strng)
{
	return	strng = strng.replace(/^\s*|\s*$/g,"");
}

function checkselect(fieldname,strng)
{
	if(strng[strng.selectedIndex].value=="")
		return("\nPlease select an options of "+fieldname);
	else
		return ("");
}