knockout.js - KnockoutJS - Computed Observables 不绑定到输入

Question

我有两个这样的模型

function CMRSerialsEditViewModel(data) {
    var self = this;
    this.CMRDeliverySerialId = ko.observable();
    this.CMRSerialNumberFrom = ko.observable();
    this.CMRSerialNumberTo = ko.observable();
    this.Count = ko.computed(function () {
        var numberfrom = Number(self.CMRSerialNumberFrom());
        var numberTo = Number(self.CMRSerialNumberTo());
        var result = numberTo - numberfrom;
      
        return result;


    });
    this.CompanyName = ko.observable();
    this.CarrierId = ko.observable();
    this.CompanySelectItems = ko.observableArray();
    this.ProductGroupId = ko.observable();
    this.ProductGroupSelectItems = ko.observableArray();
    self.LoadPrice = ko.observable();

    ko.mapping.fromJS(data, {}, this);

    this.LoadPriceFormatted = ko.computed({
        read: function () {
            return commonUtil.formatCurrency(self.LoadPrice());
        },
        write: function (value) {
            value = parseFloat(value.replace(/[^\.\d]/g, ""));
            self.LoadPrice(isNaN(value) ? 0 : value);
        },
        owner: self
    });

};

还有一个是这样的：

var CMRDeliverySerialsViewModel = function () {

    self.cmrSerial = ko.observable(new CMRSerialsEditViewModel());
   
}

在我看来，我有一个绑定到计数文件的输入文件。像这样：

                        <td>
                            <div class="editor-label">
                                <label for="CMRSerialEdit_Count">
                                    تعداد 
                                </label>
                            </div>
                        </td>
                        <td>
                            <div class="editor-field">
                                <input class="k-textbox  " id="CMRSerialEdit_Count" name="CMRSerialEdit.Count"
                                       data-bind="value:tisApp.CMRDeliverySerialsVM.cmrSerial().Count,valueUpdate: 'afterkeydown'"
                                       data-val="true" data-val-required="اين فيلد را وارد کنيد" />
                                <span class="field-validation-valid" data-valmsg-for="CMRSerialEdit.Count"
                                      data-valmsg-replace="true"></span>
                            </div>

                        </td>

一切都很好，但是当我输入 CMRSerialNumberFrom 字段和 CMRSerialNumberTo 字段时，计算了计数字段，但它没有绑定到我的视图。

一旦我在控制台中检查以下代码，它总是“0”：

tisApp.CMRDeliverySerialsVM.cmrSerial().Count