Keep getting "Uncaught TypeError: Cannot use 'in' operator to search for '191'" jQuery

Question

我正在尝试学习 jQuery AJAX，但在尝试读取 JSON 文件时不断出现相同的错误。这是 javascript 代码：

$(function (){

    var $orders = $('#orders');

    $.ajax({
        type: 'GET',
        url: '/api/orders',
        success: function(orders) {
            $.each(orders, function(i, order) {
                $orders.append('<li>my order</li>');
            });
        }


    });
});

这里是 JSON 代码：

"order":[
    {"id":1, "name":"Ben", "drink":"Americano w/ Creme"},
    {"id":2, "name":"Ben2", "drink":"Americano w/ Creme2"},
    {"id":3, "name":"Ben3", "drink":"Americano w/ Creme3"}
]

我不断收到此错误：

Uncaught TypeError: Cannot use 'in' operator to search for '191' in "order":[
    {"id":1, "name":"Ben", "drink":"Americano w/ Creme"},
    {"id":2, "name":"Ben2", "drink":"Americano w/ Creme2"},
    {"id":3, "name":"Ben3", "drink":"Americano w/ Creme3"}
]
jquery.js:584 
isArraylikejquery.js:359
jQuery.extend.eachmain.js:10
$.ajax.successjquery.js:3143
jQuery.Callbacks.firejquery.js:3255
jQuery.Callbacks.self.fireWithjquery.js:9309
donejquery.js:9713
jQuery.ajaxTransport.send.callback

有谁知道为什么我总是收到这个错误？预先感谢任何人的帮助。

Answer 1

设置dataType: 'json'，因为orders是JSON字符串而不是JS对象

 $.ajax({
     dataType: 'json',
     type: 'GET',
     url: '/api/orders',
     success: function(orders) {
         $.each(orders, function(i, order) {
             $orders.append('<li>my order</li>');
         });
     }
 });

dataType: 'json' - Evaluates the response as JSON and returns a JavaScript object.

Keep getting "Uncaught TypeError: Cannot use 'in' operator to search for '191'" jQuery

Keep getting "Uncaught TypeError: Cannot use 'in' operator to search for '191'" jQuery

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