求助：Ajax不发出任何警告，只给出404错误

我已经尝试几天了，但是Ajax还是不工作。它不会发出任何警告，只是给出了一个错误：Failed to load resource: the server responded with a status of 404 (Not Found) - [object%20Object] 它还会继续返回所有NULL、JS、PHP——不知道为什么。

JS

var fullName = ["John Doe", "Jane Doe"];

$(window).load(function(){
    getList();
});

function getList(){
    $.getJSON({
       type: "GET", /* the request's method: */
       url:"/names.php",    /* the request's location: */
       data: JSON.stringify({names: fullName}), /* the request's fields: */
       contentType: "application/json; charset=utf-8",  /* the request's content-type : */
       dataType:"json", /* the response's content-type: */
       success: function(json){ /* the callback function */
         if(json.length > 0){
             $.each(json, function(i, v){
                console.info(v);
             });
          }
          else {
             alert('wtf?!');
          }
        }
    });
}

PHP

<?php
$req=array_merge($_GET, $_POST);

$names=json_decode($req['names'], true);
header('content-type: application/json; charset=utf8;');
echo json_encode($names);

You should be using $.ajax instead of getJSON. jQuery is thinking the whole configuration object is the URL!

Also, when you change it to .ajax, you don't have to JSON.stringify the data, that will be done automatically. So the code should be:

function getList(){
    $.ajax({
       type: "GET", /* the request's method: */
       url:"/names.php",    /* the request's location: */
       data: {names: fullName}, /* the request's fields: */
       contentType: "application/json; charset=utf-8",  /* the request's content-type : */
       dataType:"json", /* the response's content-type: */
       success: function(json){ /* the callback function */
         if(json.length > 0){
             $.each(json, function(i, v){
                console.info(v);
             });
         } else {
            alert('wtf?!');
         }
       }
    });
}

A shorter version using with getJSON could be:

function getList(){
    $.getJSON("/names.php", {names: fullName}, function(json){ 
         if(json.length > 0){
             $.each(json, function(i, v){
                console.info(v);
             });
         } else {
             alert('wtf?!');
         }
    });
}

But then the requests would not be sent as JSON (only the response is expected to be JSON). So you'd need a slight change on your PHP:

<?php
$names=$_GET['names'];
header('content-type: application/json; charset=utf8;');
echo json_encode($names);

change .getJSON in your code to .ajax and the rest shoud work provided the path in URL is corret.

API DOCMENTATION

From jQuery docs, jQuery.getJSON is a shorthand of:

$.ajax({
    dataType: "json",
    url: url,
    data: data,
    success: success
});

So you should use this way:

$.getJSON('/names.php', {names: fullName}, 
    function(data) {...}
);