Send UTF8 String from UITextField over HTTP link - php

Question

I'm using php method as web service to add user_comment to mysql database.
<?php
require '../database/connection.php';
extract($_POST);
if (isset($_GET['book_ID'])) {
$book_ID = $_GET['book_ID'];
$user_ID = $_GET['user_ID'];
$theComment = $_GET['theComment'];
}
if (!$db) {
$json[] = array("Message" => "Connection failed");
echo json_encode($json);
}
$sql = mysql_query("INSERT INTO Comment (user_ID , book_ID , theComment) VALUES ('$user_ID','$book_ID','$theComment')");
mysql_query($sql, $db);
$json[] = array("Message" => "Done");
echo json_encode($json);
everything fine if I type English but I have problem with Arabic
Objective-C:
-(NSString *)addCommentForBook:(NSString *)bookID userID:(NSString *)userID theComment:(NSString *)theComment{
NSString *dt = [NSString stringWithFormat:#"?book_ID=%#&user_ID=%#&theComment=%#",bookID,userID,theComment];
NSURL *myURL = [[NSURL alloc]initWithString:[NSString stringWithFormat:#"http://www.myweb.com/library/Books/addCommentForBook.php%#",dt]];
NSMutableDictionary *theArray;
NSData *myData = [[NSData alloc]initWithContentsOfURL:myURL];
if (myData) {
id myJSON = [NSJSONSerialization JSONObjectWithData:myData options:NSJSONReadingMutableContainers error:nil];
theArray = (NSMutableDictionary *)myJSON;
}
return [[theArray valueForKey:#"Message"]objectAtIndex:0];
}
If I test from Browser work php work fine with Arabic but from iOS not work
Any one tell me what's wrong or do I need to convert the string from UITextField first or?