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?
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
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。
其他回答
几个简单的方法:
var arr = [1,2,,3,,-3,null,,0,,undefined,4,,4,,5,,6,,,,];
arr.filter(n => n)
// [1, 2, 3, -3, 4, 4, 5, 6]
arr.filter(Number)
// [1, 2, 3, -3, 4, 4, 5, 6]
arr.filter(Boolean)
// [1, 2, 3, -3, 4, 4, 5, 6]
或-(仅适用于“text”类型的单个数组项)
['','1','2',3,,'4',,undefined,,,'5'].join('').split('');
// output: ["1","2","3","4","5"]
或-经典方式:简单迭代
var arr = [1,2,null, undefined,3,,3,,,0,,,[],,{},,5,,6,,,,],
len = arr.length, i;
for(i = 0; i < len; i++ )
arr[i] && arr.push(arr[i]); // copy non-empty values to the end of the array
arr.splice(0 , len); // cut the array and leave only the non-empty values
// [1,2,3,3,[],Object{},5,6]
jQuery:
var arr = [1,2,,3,,3,,,0,,,4,,4,,5,,6,,,,];
arr = $.grep(arr, n => n == 0 || n);
// [1, 2, 3, 3, 0, 4, 4, 5, 6]
这是我清理空字段的解决方案。
从费用对象开始:仅获取可用属性(带贴图)筛选空字段(带筛选器)将结果解析为整数(带映射)
fees.map( ( e ) => e.avail ).filter( v => v!== '').map( i => parseInt( i ) );
我需要完成同样的任务,并遇到了这个线程。我最终使用数组“join”使用“_”分隔符创建字符串,然后使用正则表达式:-
1. replace "__" or more with just one "_",
2. replace preceding "_" with nothing "" and similarly
3. replace and ending "_" with nothing ""
…然后使用数组“拆分”生成一个已清理的数组:-
var myArr = new Array("","","a","b","","c","","","","","","","","","e","");
var myStr = "";
myStr = myArr.join("_");
myStr = myStr.replace(new RegExp(/__*/g),"_");
myStr = myStr.replace(new RegExp(/^_/i),"");
myStr = myStr.replace(new RegExp(/_$/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(","));
如果使用库是一个选项,我知道underscore.js有一个名为compact()的函数http://documentcloud.github.com/underscore/它还有其他几个与数组和集合相关的有用函数。
以下是他们文档的摘录:
_.compact(数组)返回删除了所有错误值的数组副本。在JavaScript中,false、null、0、“”、undefined和NaN都是假的。_.compact([0,1,false,2,'',3]);=> [1, 2, 3]
使用筛选器删除数组中的空字符串。
var s=['1201,karthikeyan,K201,直升机,karthikeyan.a@limitlessmobil.com,8248606269,7/14/201745680,TN-KAR24,88001000200300,Karthikeyan,2017年11月24日,Karthikey an,2017月11日,可用\r,'' ]var newArr=s.filter(函数(条目){return entry.trim()!=“”;})console.log(newArr);