尝试使用Knockout添加删除数据绑定功能时出错

Question

I working with Knockout and Asp.net for a project and I have some problem to add a delete action with Knockout

Everything was working fine, and the databinding doing well. But when I try to add a delete function I get this error :

JavaScript runtime error: Unable to get property 'deleteArticle' of undefined or null reference

My javascript :

    // Class to represent an article
function article(data) {
    //var self = this;

    this.id = ko.observable(data.OrderId);
    this.Type = ko.observable(data.Type);
    this.Price = ko.observable(data.Price);
    this.Quantity = ko.observable(data.Quantity);

}


    function viewModel() {
    var self = this;

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

    $.getJSON("@Url.Action("../home/AjaxArticles")", function (allData) {
        var mappedArticles = $.map(allData, function (item) { return new article(item) });
        self.Articles(mappedArticles);
    });

    // Delete an article
    self.deleteArticle = function (ArticleData) {
        self.Articles.remove(ArticleData);
    };


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

    $.getJSON("@Url.Action("../home/AjaxMoney")", function (allData) {
        var mappedMoney = $.map(allData, function (item) { return new Money(item) });
        self.MyMoney(mappedMoney);
    });


}

$(document).ready(function () {

    ko.applyBindings(viewModel);

});

And the HTML part where I use knockout:

    <tbody data-bind="foreach: Articles">
    <tr>
        <td data-bind="text: id"></td>
        <td data-bind="text: Price"></td>
        <td data-bind="text: Type"></td>
        <td data-bind="text: Quantity"></td>
        <td><a href='#' data-bind="click: $root.deleteArticle">Cancel</a></td>
    </tr>
</tbody>

What do I do wrong ?

Answer 1

You didn't instantiate your viewmodel correctly (instead, you passed in the function-object itself). When you apply your KO bindings, pass in a new instance of your viewmodel , like so:

ko.applyBindings(new viewModel());

See fiddle