var arr3=Array.prototype.push.apply(arr1,arr2); document.write(arr3);//6 document.write(arr1);//hello,world,aha!,1,2,3 var arr1=["hello","world","aha!"]; var arr2=[1,2,3]; var arr3=Array.prototype.push.call(arr1,"1","2","3","4"); document.write(arr3);//7 doc...
let arr = ['c'];arr = arr.concat(['d', 'e']);arr; // ['c', 'd', 'e']// You can also use `concat()` to add to the beginning of// the array, just make sure you call `concat()` on an array// containing the elements you want to add to the beginning.arr = ['a'...
全部Array的接口可以查看https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array let nameList = ['Brian', 'Xiang', 'Shuang'];//add item in the lastconst len = nameList.push('Ella'); console.log(nameList, len);//remove item in the lastconst poped =nameList...
let items = [10, 80, 100]; let add = (sumSoFar, item) => { return sumSoFar + item; }; let total = items.reduce(add, 0); let total1 = items.reduce(add, 10); console.log(items); //[10, 80, 100] console.log(total); //190 console.log(total1); //200 1. 2. 3. 4....
避免方法:明确splice(index, deleteCount[, item1[, ...[, itemN]]])的参数意义,特别是deleteCount表示要移除的元素数量,而非索引位置。 易错点3:修改原数组与返回值混淆 问题:部分数组方法(如splice、sort)会直接修改原数组,而有些(如concat、slice)则返回新数组。
-+-返回第一个与给定参数相等的数组元素的索引,没有找到则返回 -1。语法:array.indexOf(item,start),start选填:从下标这(包括该元素)之后的所有元素 1 2 3 letarr = ["aa","bb","cc","dd"] console.log(arr.indexOf("bb"))// 1 console.log(arr.indexOf("bb", 2))// -1 ...
Add a new item to an array: constfruits = ["Banana","Orange","Apple","Mango"]; fruits.push("Kiwi"); Try it Yourself » Add two new items to the array: constfruits = ["Banana","Orange","Apple","Mango"]; fruits.push("Kiwi","Lemon"); ...
const example1NewArray = example1Array1.concat(valuesToAdd); console.log(example1NewArray); console.log(example1Array1); 上面输出的结果: [ 1, 2, 3, 4, 5, 6 ] [ 1, 2, 3 ] 我们可以将一个数组与一系列值连接起来: const array = [1,2,3]; ...
Array在Javascript程序开发中是一个经常使用到。一个数组可以存储Javascript支持的任何数据类型。...,长度未指定 var anArray = new Array(); //为元素赋值来为数组添加新的数据项 anArray[0] = "First Item"; anArray...,其实Javascript中数组对象都是引用类型的,所以tempArray排序之后,myArray里面的数据也进行...
while(item =list.shift()) {console.log(item)} list// <- [] 5.map() 方法 签名为forEach,.map(fn(value,index,array),thisArgument)。 values= [void0,null,false,'']values[7] =void0result= values.map(function(value,index,array){console.log(va...