使用Array Some方法

 var exists = [0,1,2].some(function(count){
      return count == 1
 });

Exists将返回true，您可以将其用作函数中的变量

if(exists){
    console.log('this is true!')
}

数组一些方法- Javascript

请使用ForEach的一些或所有实例，

Array.prototype.some:
some is much the same as forEach but it break when the callback returns true

Array.prototype.every:
every is almost identical to some except it's expecting false to break the loop.

例如:

var ary = ["JavaScript", "Java", "CoffeeScript", "TypeScript"];

ary.some(function (value, index, _ary) {
    console.log(index + ": " + value);
    return value === "JavaScript";
});

每个的例子:

var ary = ["JavaScript", "Java", "CoffeeScript", "TypeScript"];

ary.every(function(value, index, _ary) {
    console.log(index + ": " + value);
    return value.indexOf("Script") > -1;
});

查找更多信息 http://www.jsnoob.com/2013/11/26/how-to-break-the-foreach/

使用Array Some方法

 var exists = [0,1,2].some(function(count){
      return count == 1
 });

Exists将返回true，您可以将其用作函数中的变量

if(exists){
    console.log('this is true!')
}

数组一些方法- Javascript

你可以用这个:

var count = 0;
var arr = [0,1,2];
for(var i in arr){
   if(count == 1) break;
   //console.log(arr[i]);
}

var ary = ["JavaScript", "Java", "CoffeeScript", "TypeScript"];
var keepGoing = true;
ary.forEach(function(value, index, _ary) {
    console.log(index)
    keepGoing = true;
    ary.forEach(function(value, index, _ary) {
        if(keepGoing){ 
            if(index==2){
                keepGoing=false;
            }
            else{
                console.log(value)
            }

        }      
    });
});

我更喜欢用return来做。将循环部分放在私有函数中，并在想要打破循环时返回。