foreach返回对象属性javascript [英] foreach return object property javascript

问题描述

在下面的代码中，有人可以解释为什么使用for循环返回object属性但不使用forEach。
它是与返回对象引用相关的东西还是特定于数组上的forEach循环的东西？

In the following code, can somebody explain why object property is returned using a for loop but not using a forEach. Is it something related to returning object references or is it something specific to forEach loop on an array ?

var empModule = (function(){
    var empArray = [{
        "name":"Aish",
        "age":"27",
        "location": "All"
    },{
        "name":"Anu",
        "age":"26",
        "location": "Muz"
    },{
        "name":"Vern",
        "age":"25",
        "location": "Mang"
    }];

    var searchAge = function(name){  
        for(var i=0;i<empArray.length;i++) {
            if(empArray[i].name === name) {
                return empArray[i].age;
            }
        };
    };

    var searchLocation = function(name){
        empArray.forEach(function(obj){
            if(name === obj.name) {
                return obj.location;
            }
        });
    };

    return {
        findAge: searchAge,
        findLocation: searchLocation
    };

})();
var secAge = empModule.findAge("Anu");
console.log(secAge); // Correct Output
var thirdLoc = empModule.findLocation("Vern");
console.log(thirdLoc); // Returns undefined

推荐答案

返回返回它所在的函数。在 for .. 示例中，那是 searchAge 。当你使用 forEach（）时，你传递一个回调函数，所以你将值返回给该回调。你永远不会在 searchLocation 中返回任何内容。

return returns to the function it's in. In the for.. example, that's searchAge. When you use forEach(), you pass it a callback function, and so you return the value to that callback. You never return anything in searchLocation.

你应该只使用常规来... 在这里循环两次。

You should just use the regular for.. loop both times here.

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