如何在JavaScript中删除数组中的空元素?

是否有一种简单的方法,或者我需要循环并手动删除它们?


当前回答

试试这个。将数组传递给它,它将返回并删除空元素*更新以解决Jason指出的错误

function removeEmptyElem(ary) {
    for (var i = ary.length - 1; i >= 0; i--) {
        if (ary[i] == undefined)  {
            ary.splice(i, 1);
        }       
    }
    return ary;
}

其他回答

如果有人想要清理整个阵列或对象,这可能会有所帮助。

var qwerty = {
    test1: null,
    test2: 'somestring',
    test3: 3,
    test4: {},
    test5: {
        foo: "bar"
    },
    test6: "",
    test7: undefined,
    test8: " ",
    test9: true,
    test10: [],
    test11: ["77","88"],
    test12: {
        foo: "foo",
        bar: {
            foo: "q",
            bar: {
                foo:4,
                bar:{}
            }
        },
        bob: {}
    }
}

var asdfg = [,,"", " ", "yyyy", 78, null, undefined,true, {}, {x:6}, [], [2,3,5]];

function clean_data(obj) {
    for (var key in obj) {
        // Delete null, undefined, "", " "
        if (obj[key] === null || obj[key] === undefined || obj[key] === "" || obj[key] === " ") {
            delete obj[key];
        }
        // Delete empty object
        // Note : typeof Array is also object
        if (typeof obj[key] === 'object' && Object.keys(obj[key]).length <= 0) {
            delete obj[key];
        }
        // If non empty object call function again
        if(typeof obj[key] === 'object'){
            clean_data(obj[key]);
        }
    }
    return obj;
}

var objData = clean_data(qwerty);
console.log(objData);
var arrayData = clean_data(asdfg);
console.log(arrayData);

输出:

删除任何null、undefined、“”、“”空对象或空数组

jsfiddle在这里

这个呢(ES6):从数组中删除Falsy值。

var arr = [0,1,2,"test","false",false,true,null,3,4,undefined,5,"end"];

arr.filter((v) => (!!(v)==true));

//output:

//[1, 2, "test", "false", true, 3, 4, 5, "end"]

试试这个。将数组传递给它,它将返回并删除空元素*更新以解决Jason指出的错误

function removeEmptyElem(ary) {
    for (var i = ary.length - 1; i >= 0; i--) {
        if (ary[i] == undefined)  {
            ary.splice(i, 1);
        }       
    }
    return ary;
}
var data= { 
    myAction: function(array){
        return array.filter(function(el){
           return (el !== (undefined || null || ''));
        }).join(" ");
    }
}; 
var string = data.myAction(["I", "am","", "working", "", "on","", "nodejs", "" ]);
console.log(string);

输出:

我正在研究nodejs

它将从数组中删除空元素并显示其他元素。

我需要完成同样的任务,并遇到了这个线程。我最终使用数组“join”使用“_”分隔符创建字符串,然后使用正则表达式:-

1. replace "__" or more with just one "_",
2. replace preceding "_" with nothing "" and similarly 
3. replace and ending "_" with nothing ""

…然后使用数组“拆分”生成一个已清理的数组:-

var myArr = new Array("","","a","b","","c","","","","","","","","","e","");
var myStr = "";

myStr = myArr.join("_");

myStr = myStr.replace(new RegExp(/__*/g),"_");
myStr = myStr.replace(new RegExp(/^_/i),"");
myStr = myStr.replace(new RegExp(/_$/i),"");
myArr = myStr.split("_");

alert("myArr=" + myArr.join(","));

…或1行代码:-

var myArr = new Array("","","a","b","","c","","","","","","","","","e","");

myArr = myArr.join("_").replace(new RegExp(/__*/g),"_").replace(new RegExp(/^_/i),"").replace(new RegExp(/_$/i),"").split("_");

alert("myArr=" + myArr.join(","));

…或,扩展Array对象:-

Array.prototype.clean = function() {
  return this.join("_").replace(new RegExp(/__*/g),"_").replace(new RegExp(/^_/i),"").replace(new RegExp(/_$/i),"").split("_");
};

var myArr = new Array("","","a","b","","c","","","","","","","","","e","");

alert("myArr=" + myArr.clean().join(","));