Question

这让我发疯了...我在这里检查了很多与我的问题相关的帖子，但仍无法解决我的问题。简而言之：我使用'$ .Ajax.BeginForm'来更新我的模型observableArray。数据在那里，表被更新，但是，当我检查该数组的长度时，它保持为0！我在这里想念的是什么？

这是数据：

视图模型：

<script type="text/javascript">
        //VIEW MODEL DECLARATION:
        var ViewModel = {
            SubscriberEmail: ko.observable(""),
            SubscriberLists: ko.observableArray([]),
            UnsubscribeAll: ko.observable(false),
            UpdateSubscriberLists: function ()
            {
                $.ajax("/Home/UpdateSubscriptionInfo/", {
                    data: ko.toJSON({ lists: this.SubscriberLists }),
                    type: "post",
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    success: function (data)
                    {
                        $().toastmessage('showNoticeToast', data);
                    }
                });
            },
            ProcessUnsubscribeAll: function() {
                if (this.UnsubscribeAll)
                {
                    alert('changing');
                    alert(ViewModel.SubscriberLists().length);
                    ko.utils.arrayForEach(ViewModel.SubscriberLists(), function (item)
                    {
                        alert("changing OptIn");
                        //item.OptIn = false;
                    });
                };
            }
        };

        //UTILITY FUNCTIONS:
        function DisplayMessage(data)
        {
            $().toastmessage('showNoticeToast', data);
        }
        function ProcessListsReceived(data)
        {
            ViewModel.SubscriberLists(ko.mapping.fromJSON(data));
        }

        //ON DOCUMENT LOADED:
        $(document).ready(function ()
        {
            ko.applyBindings(ViewModel);
        });
    </script>

要求更新的部分：

<div class="navbar-right form-inline" style="margin-top: 10px;">
                @using (Ajax.BeginForm("GetSubscriptionInfo",
                                       new AjaxOptions
                                           {
                                               HttpMethod = "POST",
                                               OnSuccess = "ProcessListsReceived"
                                           }))
                {
                    <div class="form-group">
                        <span class="glyphicon glyphicon-search">&nbsp;</span>
                        <label class="sr-only" for="inputemail">Email address</label>
                        <input data-bind="text:SubscriberEmail" type="email" class="form-control input-sm" id="inputemail" name="inputemail" placeholder="Enter your email" style="width: 300px;">
                    </div>
                    <button type="submit" class="btn btn-default input-sm btn-primary" data-loading-text="Loading...">Get my subscriptions</button>
                }
            </div>

在Javascript部分更新上面声明的可观察数组的函数 -

 function ProcessListsReceived(data)
            {
                ViewModel.SubscriberLists(ko.mapping.fromJSON(data));
            }

我有一个绑定到数组长度的按钮..它总是保持禁用状态：

<button data-bind="click: UpdateSubscriberLists, enable: SubscriberLists().length > 0" type="button" class="btn btn-warning">Update subscription</button>

SO ....为什么更新后数组长度为0？谢谢你的任何提示!!

AL

Answer 1

好的，似乎'ko.mapping.fromJSON'在我的情况下不会更新我的数组的长度... 重写代码进行实际推送就可以了，我的数组正确反映了元素的数量。

所以而不是：

 function ProcessListsReceived(data)
            {
                ViewModel.SubscriberLists(ko.mapping.fromJSON(data));
            }

我已声明：

 var SubscriberList = function (id,name,desc,optin) {
            this.ListID = ko.observable(id);
            this.ListName = ko.observable(name);
            this.ListDescription = ko.observable(desc);
            this.OptIn = ko.observable(optin);
        };

并将该函数重写为：

function ProcessListsReceived(data) {
            $(jQuery.parseJSON(data)).each(function ()
            {
                ViewModel.SubscriberLists.push(new SubscriberList(this.ListID, this.ListName, this.ListDescription, this.OptIn));
            });
        }

现在可以了。谢谢，人

ObservableArray.length保持为0. Knockout

1 个答案: