//colors row bgcolor
function colorrow(rowid,rowcolor) {
	document.getElementById(rowid).style.backgroundColor=rowcolor;	
}
//checks if variable is an integer
function isint(qty) { 
	var myMod=qty % 1; 
	if (myMod==0) { return true; } else { return false; } 
}
//gets extension filename
function getextfname(imgfname) { 
	indexEnd=imgFname.length; 
	indexStart=indexEnd-3; 
	extFname=imgFname.substr(indexStart,indexEnd); 
	return extFname; 
}
//removes preceding/succeeding blank characters
function trimstr(val) { 
	val=val.replace( /^\s+/g, "" ); 
	return val.replace( /\s+$/g, "" ); 
}
//checks if variable is empty
function isempty(val) {	
	return trimstr(val)==''; 
}
//checks if email is in valid format
function isemail(val) { 
	var regex=new RegExp('[\\w\\.-]+(\\+[\\w-]*)?@([\\w-]+\\.)+[\\w-]+'); 
	return val.match(regex); 
}
//checks if date is in valid mysql datetime field format
function isdate(val) { 
	var regex=new RegExp('^([0]?[1-9]|[1][0-2])[./-]([0]?[1-9]|[1|2][0-9]|[3][0|1])[./-]([0-9]{4}|[0-9]{2})$'); 	
	return val.match(regex);
}
//checks if file is a valid image file (jpg, gif or png)
function isimage(val) {	
	var img=val; 
	var lastDot=img.lastIndexOf('.'); 
	var valid=true; 
	if(lastDot>0&&lastDot<(img.length-1)) { 
		var ext=img.substring(lastDot+1); 
		if (!(ext=='jpg'||ext=='gif'||ext=='png')) valid=false;		
	} return valid; 
}