jQuery Deferred and promise - Error: Object doesn't support property or method 'then'

Question

我可能在这里遗漏了一些非常基本的东西，但我似乎找不到错误，这让我很沮丧。我只是想从我的开发 SharePoint 网站中提取列表（然后是项目，但这里一次提取一件事）。

我已经构建了第一个延迟方法，控制台日志显示它已完成，但随后我得到 "Error: Object doesn't support property or method 'then'"，好像 jQuery 不知何故失败了。

作为参考，我正在尝试遵循此处描述的方法：http://www.shillier.com/archive/2013/03/04/using-promises-with-the-javascript-client-object-model-in-sharepoint-2013.aspx

代码如下：

<script src="jquery-1.11.2.js"></script>
<script type="text/javascript">

    $(function () {

        GetSiteLists.bListsGotten().then(
            function (oWebLists) {
                // Get Lists Succeeded
                alert('Lists Retrieved');
            }
            , function (sender, args) {
                // Get Lists Failed
                alert('Lists Not Retrieved');
            }
        );

    });

    GetSiteLists = function () {
        var bListsGotten = function () {

            var deferred = $.Deferred();

            var oContext = new SP.ClientContext.get_current();
            console.log('oContext instantiated');
            var oWeb = oContext.get_web();
            console.log('oWeb instantiated');
            this.oWebLists = oWeb.get_lists();
            console.log('oWebLists command set');
            oContext.load(this.oWebLists);
            console.log('context load command set');
            oContext.executeQueryAsync(
                Function.createDelegate(this,
                    function () { deferred.resolve(this.oWebLists); }),
                Function.createDelegate(this,
                    function (sender, args) { deferred.reject(sender, args); }));
            console.log('list retrieval query executed async');

            console.log('returning promise');
            return deferred.promise;
        }

        return {

            bListsGotten: bListsGotten
        }
    }();

</script>

Answer 1

promise 是一个函数，您没有调用它。

return deferred.promise()

会解决这个问题。

jQuery Deferred and promise - Error: Object doesn't support property or method 'then'

jQuery Deferred and promise - Error: Object doesn't support property or method 'then'

javascript

jquery

csom