javascript - Backbone 中出现奇怪的错误 : Uncaught SyntaxError: Unexpected token B

Question

Uncaught SyntaxError: Unexpected token Bn.get_api_token 
@ ain.js:14s.sync 
@ services.js:10i.Model.extend.sync 
@ UserHeaderModel.js:13n.extend.fetch 
@ backbone.js:599i.View.extend.initialize 
@ UserHeaderView.js:13e.View 
@ backbone.js:1192i 
@ backbone.js:1852e.exports.i.View.extend.initialize
@ HeaderView.js:16e.View 
@ backbone.js:1192i 
@ backbone.js:1852i.Router.extend.initialize 
@ router.js:14e.Router 
@ backbone.js:1440i 
@ backbone.js:1852a.init 
@ app.js:10o.1../router 
@ app.js:39r 
@ _prelude.js:1t 
@ _prelude.js:1(anonymous function) 
@ _prelude.js:1

一切都工作正常，直到某个时候，但现在我收到这个奇怪的错误:

Uncaught SyntaxError: Unexpected token B

我的 services.js 代码:

    var $ = jQuery = require('jquery'),
    Handlebars = require('handlebars'),
    Backbone = require('backbone'),
    mainJs = require('./main');

var services = {

    sync: function (method, model, options) {
        var self = this;
        var api_token = mainJs.get_api_token();
        var access_token;
        if (api_token == null) {
            access_token = api_token;

        } else {
            access_token = api_token.access_token;
        }

        options || (options = {});

        var beforeSend = options.beforeSend;
        options.beforeSend = function (xhr) {
            xhr.setRequestHeader('Authorization', 'Bearer ' + access_token)
            if (beforeSend) return beforeSend.apply(this, arguments);
        };

        switch (method) {
            case "read":
                options.url = options.readUrl;
                break;
            case "delete":
                options.url = options.deleteUrl;
                break;
            case "update":
                options.url = options.updateUrl;
                options.contentType = 'application/json';
                break;
            case "create":
                options.url = options.createUrl;
                options.contentType = 'application/json';
                break;
        }

        options.error = function (xhr, statusTxt, thrown) {
            switch (xhr.status) {
                case 401:
                    console.log("Unauthorized error");
                    break;
                default:
                    var messageText = JSON.parse(xhr.responseText);;
                    console.log("Status code: " + xhr.status + " Error: " + messageText.message);
            }
        }

        if (options.url)
            return Backbone.sync.call(model, method, model, options);

    }

}


module.exports = services;

main.js

    var mainJs = {
    get_api_token: function () {
        var apiat = null;
        var cookies = document.cookie.split(";");
        for (var i = 0; i < cookies.length; ++i) {
            var kv = cookies[i].split("=");
            if (kv[0].trim() === "API") {
                apiat = kv[1].trim();
                break;
            }
        }
        if (apiat) {
            return JSON.parse(apiat);
        }
        return null;
    }
}

module.exports = mainJs;

请帮忙

Answer 1

您的 JSON.parse(apiat) 可能正在解析非 JSON 的内容。

如果你打印 apiat 你就会发现你的问题。

一个好的做法是始终将 JSON.parse 包装在 try {} catch () 子句中:

try {
    JSON.parse(data);
} catch (e) {
    console.log('Error parsing JSON', e);
}