จาก link การใช้ ajax เช็ค username จะทำอย่างไรให้เช็คค่าที่ไม่ใช่ภาษาอังกฤษได้ด้วย

<?php
	/*** By Weerachai Nukitram ***/
	/***  http://www.ThaiCreate.Com ***/

	$strUsername = trim($_POST["tUsername"]);

	if(trim($strUsername) == "")
	{
		echo "<img src='img/false.png'>";
		exit();
	}

	

	$objConnect = mysql_connect("localhost","root","root") or die("Error Connect to Database");
	$objDB = mysql_select_db("mydatabase");

	//*** Check Username (already exists) ***//

	$strSQL = "SELECT * FROM account WHERE Username = '".$strUsername."' ";
	$objQuery = mysql_query($strSQL) or die ("Error Query [".$strSQL."]");
	$objResult = mysql_fetch_array($objQuery);
	if($objResult)
	{
		echo "<img src='img/false.png'>";
	}
	else
	{
		echo "<img src='img/true.png'>";
	}

	mysql_close($objConnect);
?>

echo "<img src='img/false.png'>";