用无序列表敲除列表绑定

Question

我真的很新，我遇到了列表绑定的问题。

   var RequiredItemLine = function () {

            var self = this;
            self.editable = ko.observable(0);
            self.desc = ko.observable();
            self.key = ko.observable();

            self.requireditems = ko.observableArray([
                  { desc: "Boarding of exposed wall openings in the vicinity of ...", key: "233" },
                  { desc: "Call in manufacturers to initiate repairs on ...", key: "242" },
                  { desc: "Call in specialist restorers/recoverers for ...", key: "244" },
                  { desc: "Dispatch items for repair (schedule enclosed)", key: "243" },
                  { desc: "Drying and cleaning of contents comprising ...", key: "240" },
                  { desc: "Drying and protective oiling of water affected equipment", key: "241" },
                  { desc: "Drying out of the affected areas of the premises", key: "235" },
                  { desc: "Removal and repackaging of stock comprising ...", key: "239" },
                  { desc: "Removal of agreed vulnerable contents to a place of safety (schedule enclosed) ", key: "236" },
                  { desc: "Segregation of affected and unaffected stock comprising ...", key: "238" },
                  { desc: "Temporary covering of roof to reinstate water tight integrity ", key: "234" },
                  { desc: "Temporary guarding of affected area", key: "237" },
                  { desc: "Temporary shoring of affected structure", key: "232" }]);

            self.selectedItem = ko.observable(self.requireditems()[0]);



            self.selectedItem.subscribe(function (newValue) {

                var li = "<li>" + newValue.desc + "</li>";

                $('#items').append(li);


            });       
        };


        var RequiredItem = function () {

            var self = this;

            self.requireditemSelection = ko.observableArray([]); // Put one line in by default


            self.requireditemlines = ko.observableArray([]);

            // Operations
            self.addRequiredItem = function () { self.requireditemSelection.push(new RequiredItemLine()) };
            self.RemoveRequiredItem = function (line) { self.requireditemSelection.remove(line) };


        };


        ko.applyBindings(new RequiredItem());

请看这个小提琴。 JSFiddle Link，在页面中包含一个添加选择列表的按钮，当点击一个按钮时，新的选择列表将被添加到DOM。当用户从一个选择列表中选择项目时，所选项目应该单独显示，并且当用户改变时，已经显示在DOM中的所选项目必须根据选择而改变，而不是附加新的li。 / p>

请看第二张图片，我不想显示另一个列表项，而不是我想要更改当前添加的项目。

Answer 1

我觉得你很亲密。我不是100％确定我是否正确理解了您的问题，我已将您的问题解释为“想要在只读列表中显示所有选定的项目”。

请参阅updated fiddle，其中我只是将ul更改为：

<ul data-bind='foreach: requireditemSelection'>
    <li data-bind="text: selectedItem().desc"></li>
</ul>  

您无需手动创建li项并将其添加到DOM。让KO为您处理，并且数据绑定只读项目。