function fetch_object(idname){
	if (document.getElementById){
		return document.getElementById(idname);}
	else if (document.all){
		return document.all[idname];}
	else if (document.layers){
		return document.layers[idname];}
	else{
		return null;}
}

function CheckAllCheckbox(f,checkboxname){
	var len=f.elements.length;
	for(var i=0;i<len;i++){
		if(f.elements[i].name==checkboxname){
			f.elements[i].checked=true;
		}
	}
	return;
}

//-------------------------------------------------------------------------------------------
function UnCheckAllCheckbox(f,checkboxname){
	var len=f.elements.length;
	for(var i=0;i<len;i++){
		if(f.elements[i].name==checkboxname){
			f.elements[i].checked=false;
		}
	}
	return;
}

//------------------------------------------------
function LTrim(Str) {
	return Str.replace(/^\s+/, '');
}

//------------------------------------------------
function RTrim(Str) {
	return Str.replace(/\s+$/, '');
}
//------------------------------------------------
function Trim(Str) {
	return RTrim(LTrim(Str));
}
//-------------------------------------------------------------------------------------------
function isEmpty(Str) {
	empty = (Str === "") ? true :  false;
	return empty;
}

//-------------------------------------------------------------------------------
function isNumber(Digit) {
	return /^\d+[\.\d*]?$/.test(Digit);
}

//------------------------------------------------------------------------------
function isAlphabet(Digit) {
	return /^[a-zA-Z]$/.test(Digit);
}

//-------------------------------------------------------------------------------
function isInteger(Str) {
	return /^[+-]?\d+$/.test(Str);
}

//-------------------------------------------------------------------------------
function isFloat(Str) {
		return /^[+-]?\d+\.{1}\d*$/.test(Str);
}

//-------------------------------------------------------------------------------
function isCurrency(Str) {
		return /^\d+[.]{1}[0-9]{2,}$/.test(Str);
}

function isDomain (Str) {
	// The pattern for matching all special characters. 
  	//These characters include ( ) < > [ ] " | \ / ~ ! @ # $ % ^ & ? ` ' : ; , 
	var specialChars="\\(\\)<>#\\$&\\*!`\\^\\?~|/@,;:\\\\\\\"\\.\\[\\]";
	// The range of characters allowed in a username or domainname. 
	// It really states which chars aren't allowed. 
	var validChars="\[^\\s" + specialChars + "\]";
	 // An atom (basically a series of  non-special characters.) 
	var atom=validChars + '+';
	// The structure of a normal domain 
	var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");
	
	// Check if IP
	var ipDomainPat=/^(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/;
	var IPArray=Str.match(ipDomainPat);
	if (IPArray!=null) {
  	// this is an IP address
	 	 for (var i=1;i<=4;i++) {
	    		if (IPArray[i]>255) {
	 			return false
	   		 }
   		 }
	}
	// Check Domain
	var domainArray=Str.match(domainPat)
	if (domainArray==null) {
    		return false;
	}

	/* domain name seems valid, but now make sure that it ends in a
	 three-letter word (like com, edu, gov ... ) or a two-letter word,
   	representing country (uk, vn) or a four-letter word (.info), and that there's a hostname preceding 
   	the domain or country. */

	/* Now we need to break up the domain to get a count of how many atoms
	it consists of. */
	var atomPat=new RegExp(atom,"g")
	var domArr=Str.match(atomPat)
	var len=domArr.length
	if (domArr[domArr.length-1].length<2 || domArr[domArr.length-1].length>4) {
	 // the address must end in a two letter or three letter word or four-letter word.
		return false;
	}

	// Make sure there's a host name preceding the domain.
	if (len<2) {
   		 return false;
	}

	return true;
}

function isUser (Str) {
	var specialChars="\\(\\)<>#\\$&\\*!`\\^\\?~|/@,;:\\\\\\\"\\.\\[\\]";
	var validChars="\[^\\s" + specialChars + "\]";
	/* The pattern applies if the "user" is a quoted string (in
   	which case, there are no rules about which characters are allowed
   	and which aren't; anything goes).  E.g. "le nguyen vu"@webtome.com
   	is a valid (legal) e-mail address. */
	var quotedUser="(\"[^\"]*\")";
	var atom=validChars + '+'
	var word="(" + atom + "|" + quotedUser + ")";
	var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
	// See if "user" is valid 
	if (Str.match(userPat)==null) {
    		return false ;
	}
	return true;
}

function isEmail (emailStr) {
	/* The pattern for matching fits the user@domain format. */
	var emailPat=/^(.+)@(.+)$/ ;
	var matchArray=emailStr.match(emailPat);
	if (matchArray==null) {
 	 /* Too many/few @'s or something; basically, this address doesn't
    	 even fit the general mould of a valid e-mail address. */
		return false;
	}
	var user=matchArray[1];
	var domain=matchArray[2];

	// See if "user" is valid 
	if (!isUser(user)) {
    	// user is not valid
   		 return false ;
	}

	// Check Domain
	if (!isDomain(domain)) {
   		return false;
	}
	return true;
}

function openNewWindow(linkurl,imgh,imgw,s) {
	var w = screen.availWidth;
	var h = screen.availHeight;
	var leftPos = (w-imgw)/2, topPos = (h-imgh)/2;
	window.open(linkurl,'popup','location=0,status=0,scrollbars='+s+',width=' + imgw + ',height=' + imgh + ',top=' + topPos + ',left=' + leftPos);
}

function getExtension(fileName){
		return fileName.substr(fileName.lastIndexOf(".")+1);
}