不确定如何将方法定义转换为ES6

Question

I'm currently in the process of converting our Backbone application to ES6 syntax like eg this:

action: function(e){},

Becomes

action(e) {}

However, now I'm having this code:

throttleEvent: _.throttle(function(e) {
    //do stuff
    }, 500);
}

And I can't seem to find how to convert this to valid syntax. I tried

throttleEvent _.throttle((e) => {
    //do stuff
    }, 500);
}

And

throttleEvent() {
    return _.throttle((e) => {
    //do stuff
    }, 500);
}

But these all failed to work.

Help converting this to the valid syntax would be appreciated.

Answer 1

Well I'm not quite sure if the short syntax is applicable for your example.

Lets have a look at your start

action: function(e){},

you have an object, that object has a property called "action" and that property holds a function that later then can be called by obj.action().

Now to your example

throttleEvent: _.throttle(function(e) {}

Again you have an object, that has a property called throttleEvent. But the main difference is the value. The value is the return Value of the function _.throttle().

Taking from the documentation ( https://lodash.com/docs/4.17.4#throttle )

Creates a throttled function that only invokes func at most once per every wait milliseconds

So your property actually holds the function that you got returned from the library. That explains why your second approach does not work. Because in this version every time you call the object property, you create a new throttle function. (And to your first solution I think this is invalid syntax)

I think the best approach if you really want to use the short syntax is, assigning the throttle function to a variable before and then use it

For example something like this

const throttleFunction = _.throttle((event) => {
    //do stuff
}, 500);
const obj = {
    throttleEvent(event): any {
        return throttleFunction(event);
    },
};

But then it is to decide whether the ES6 syntax makes sense in this case or if you just stick with your original version

throttleEvent: _.throttle(function(e) {
    //do stuff
    }, 500)

Just because there is a different syntax available, does not mean you always have to use the new one. In some cases the "old one" makes actually more sense

Answer 2

试试这个语法：

_.throttle(() => //Do stuff, 5000)