Javascript KnockoutJS:单击Select中每个选项上调用的事件
我希望Knockout在用户单击SELECT元素中的选项时调用事件 以下是我的JavaScript:Javascript KnockoutJS:单击Select中每个选项上调用的事件,javascript,knockout.js,Javascript,Knockout.js,我希望Knockout在用户单击SELECT元素中的选项时调用事件 以下是我的JavaScript: function ReservationsViewModel() { this.availableMeals = [ { mealName: "Standard (sandwich)", price: 0 }, { mealName: "Premium (lobster)", price: 34.95 }, { mealName: "Ult
function ReservationsViewModel() {
this.availableMeals = [
{ mealName: "Standard (sandwich)", price: 0 },
{ mealName: "Premium (lobster)", price: 34.95 },
{ mealName: "Ultimate (whole zebra)", price: 290 }
];
}
ko.applyBindings(new ReservationsViewModel());
这是我的HTML:
<select data-bind="foreach: availableMeals">
<option data-bind="text: mealName, click: alert('hello')" />
</select>
但是当我运行这个程序时,应用程序显示“hello”三次,即使没有实际单击任何选项
我做错了什么?您应该使用
change
绑定而不是单击和选项text
绑定而不是选项
标记并在change
绑定中使用函数
,而不是仅仅调用警报
:
<select data-bind="options: availableMeals, optionsText: 'mealName', value: selectedMeal, event: {change: onChange}">
</select>
function Meal(name, price){
var self = this;
self.mealName = name;
self.price = price;
}
function ReservationsViewModel() {
var self = this;
self.availableMeals = ko.observableArray(
[new Meal("Standard (sandwich)", 0),
new Meal("Premium (lobster)", 34.95),
new Meal("Ultimate (whole zebra)", 290)]);
self.selectedMeal = ko.observable(self.availableMeals()[0]);
self.onChange = function() {
alert("Hello");
};
}
ko.applyBindings(new ReservationsViewModel());
功能餐(名称、价格){
var self=这个;
self.mealName=名称;
self.price=价格;
}
函数ReservationsViewModel(){
var self=这个;
self.availableMeals=ko.observableArlay(
[新餐(标准(三明治)”,0,
新餐(“优质(龙虾)”,34.95),
新餐(“终极(全斑马)”,290);
self.selectedMeal=ko.observable(self.availableMeals()[0]);
self.onChange=函数(){
警惕(“你好”);
};
}
应用绑定(新的ReservationsViewModel());
下面是一个工作示例:应将“警报”嵌入函数中:
<select data-bind="foreach: availableMeals, event: {change: function () { alert('hello'); } }">
<option data-bind="text: mealName " />
</select>
工作得非常完美,而且是一种更为复杂的模式。谢谢是的,这太完美了!很好的KO模式示例