A question about Ajax, to help you look at what's happening

A question about Ajax, help to see what the situation is
HTML code:

Member ID:



JS Code:
function Get_user_jifen (user_name) {
if (user_name = = "") {
document.getElementById (' User_jifen '). InnerHTML = "User name cannot be empty";
$ ("#user_jifen"). HTML ("User name cannot be empty");
return false;
} else {
$.ajax ({
Type: "POST",
URL: "user_jifen.php",
DataType: "HTML",
Data: "Act=ajax&user_name=" +user_name,
Success:function (msg) {
$ ("#user_jifen"). HTML (msg);
},
Error:function ()
{
$ ("#user_jifen"). HTML ("query error");
}
});
}
}

PHP Code:
Redeem Loyalty points for Ajax
ElseIf ($_request[' act '] = = ' Ajax ')
{
/* Permission's judgment */
Admin_priv (' logs_manage ');
/* Template Assignment */
echo "Successful entry";
}


After running, always in the AJAX block into the error prompt:



Help to see, how to solve?

------Solution--------------------
Try $_post.
Or never even entered the ElseIf.
------Solution--------------------
User_jifen.php does not exist

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