jQuery:从触发器返回值 [英] Jquery: Returning Value From Trigger

问题描述

我正在使用触发器调用从自定义事件中获取值，但是我希望它返回一个值，并且在执行以下调用时它仅给我Object对象:

I am using a trigger call a get a value from custom event but I want it to return a value and its only giving me Object Object when I do the following call:

var user_id=$("#my_div").trigger("get_id", [username]);

我的触发事件函数如下:

My trigger event function looks like this:

$("#my_div").on("get_id", function(e, username){
    var user_id;
    if (username='fred'){
        user_id=1;
    }
    else if(username='mario'){
        user_id=2;
    }
    return user_id;
});

推荐答案

您不能从触发器返回值，但是可以用许多不同的方式存储信息，一种方式是将对象用作参数:

You cannot return a value from a trigger, but you can store information in many different ways, one way is using a object as a parameter:

//event
$("element").on("click", function(event, informationObj) {
       informationObj.userId = 2; //you have to access a propery so you can modify the original object
});
//trigger
var informationObj = {userId : 0};
$("element").trigger("click", [informationObj ]); //informationObj.userId === 2

另一种方法是使用jQuerys .data()方法

other way is using jQuerys .data() method

//event
$("element").on("click", function() {
     $(this).data("userId", 2); 
});
//trigger
$("element").trigger("click").data("userId") //2

您可以做的另一件事是修改在事件外部声明的变量，然后在调用触发器后使用它，或将其作为属性存储在具有这样的关键字:

Another thing you can do is modifying a variable that's declared outside the event and then using it after calling the trigger, or storing it as a property in the element that has the event with the this keyword like this:

//inside the event function
this.userId = 2;

//outside the event
$("element").trigger("click").get(0).userId

希望有帮助.

此外，请使用.triggerHandler()在下面查看 @ Arm0geddon答案，只是要注意它具有某些方面效果，例如不冒泡DOM层次结构.

Also, take a look at @Arm0geddon answer below, using .triggerHandler(), just beware that it has some side effects, like not bubbling up the DOM hierarchy.

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