[Original] Ajax implementation of user registration function tutorial three_PHP tutorial

//[Original] Ajax implementation of user registration function tutorial three

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Now in the third step, let’s write the type.php file. The function of this file is to determine whether the user name exists, and then give the data to the user.

header("Content-type:text/html;charset=gb2312");//In order to prevent it from being garbled, the document encoding is set to gb2312
$xm=Strreplace(isset($_GET['txt'])?$_GET['txt']:'null');//Get username
if(preg_match("/^[".chr(0xa1)."-".chr(0xff)."]+$/", $xm)){//Determine whether the first user name is a Chinese character,
echo("