javascript - Knockout.js : manually trigger computed

我在页面上有一个网格和一个选择控件。选择任何选择值都会触发网格更新。该更新是使用计算完成的。例如，当将新值添加到网格时，是否可以手动触发网格以进行更新？

 function vm(){
    var self = this;

    self.items = ko.observableArray([]);
    self.chosen_category = ko.observable("");

    self.pager = {
        page_namber : ko.observable(1),
        page_size : ko.observable(10)
    };

     self.sort = {
       field : ko.observable('name'),
       dist : ko.observable('asc')
     };
     // etc.

     self.fetch = ko.computed(function(){
        $.ajax({
               url: '/api/items/',
               type: 'GET',
               data: ko.toJSON(self),
               contentType: 'application/json',
               success: self.items
          });
     }, self);


      self.add_item = function() {
        //here I want to update the grid
        self.fetch(); // not work
      };
 }

当然可以将其移至单独的功能，但我正在寻找更清洁的解决方案。
谢谢!

工作版本:

          function vm() {
            var self = this;

            self.items = ko.observableArray([]);
            self.chosen_category = ko.observable("test");

            self.pager = {
                page: ko.observable(1),
                size: ko.observable(10)
            };

            self.sort = {
                field: ko.observable('name'),
                dist: ko.observable('asc')
            };

            self.fetch = function () {
                var data = {
                    category: self.chosen_category(),
                    pager: ko.toJS(self.pager),
                    sort: ko.toJS(self.sort)
                };

                $.ajax({
                    url: '/api/items/',
                    type: 'POST',
                    data: ko.toJSON(data),
                    contentType: 'application/json',
                    success: self.items
                });
            };

            self._auto_update = ko.computed(self.fetch).extend({ throttle: 1 }); ;

            self.add_item = function () {
                self.fetch();
            };
        }

最佳答案

最好使用subscription而不是computed做到这一点。在这种情况下，您可以定义获取功能以用于预订和手动调用:

function vm(){
  var self = this;

  self.items = ko.observableArray([]);
  self.chosen_category = ko.observable("");

  self.fetch = function(){
    $.get('/api/items/' + self.chosen_category(), self.items);
  };

  self.chosen_category.subscribe(self.fetch);


  self.add_item = function() {
   //here I want to update the grid
   self.fetch();
  };
}

您也可以对compute执行相同的操作:

function vm(){
  var self = this;

  self.items = ko.observableArray([]);
  self.chosen_category = ko.observable("");

  self.fetch = function(){
    $.get('/api/items/' + self.chosen_category(), self.items);
  };

  self.doStaff = ko.computed(self.fetch);


  self.add_item = function() {
   //here I want to update the grid
   self.fetch();
  };
}

关于javascript - Knockout.js : manually trigger computed，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/13836351/