The map() method creates a new array with the results of calling a function for every array element.The map() method calls the provided function once for each element in an array, in order.Note: map() does not
JavaScript Array 对象 实例 返回一个数组,数组中元素为原始数组的平方根: varnumbers = [4,9,16,25]; functionmyFunction() { x = document.getElementById("demo") x.innerHTML = numbers.map(Math.sqrt); } 输出结果为: 2,3,4,5 尝试一下 » ...
The Array keys() Method The Array map() Method Syntax array.map(function(currentValue, index, arr), thisValue) Parameters ParameterDescription function()Required. A function to be run for each array element. currentValueRequired. The value of the current element. ...
array.map(function(currentValue,index,arr),thisValue) 其中function的三个参数分别是: 实例: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 letarrMap:Array<string>=['1','2','3','a','b','c']letnewArr:Array<string>=arrMap.map((currentValue:string,index:number,arr:Array<string>)=>{...
JavaScript Array map() 方法 一、定义 map() 方法返回一个新数组,不会改变原始数组。同时新数组中的元素为原始数组元素调用函数处理后的值,并按照原始数组元素顺序依次处理元素。 注意:map() 不会对空数组进行检测。 二、语法 array.map(function(currentValue,index,arr),thisValue)...
var word = "Thursday"; // Apply the map method to the string. // Each array element in the result contains a string that // has the previous, current, and next character. // The commented out statement shows an alternative syntax. var result = [].map.call(word, threeChars); // ...
}// Create a string.varword ="Thursday";// Apply the map method to the string.// Each array element in the result contains a string that// has the previous, current, and next character.// The commented out statement shows an alternative syntax.varresult = [].map.call(word, threeChars...
In this tutorial, we will learn about the JavaScript Array map() method with the help of examples. In this article, you will learn about the map() method of Array with the help of examples.
语法:array.map(function(value,index,array){return...})value:必须。当前元素的值index:可选。当前元素的索引值array:可选。当前元素属于的数组对象 实例: vararr=[1,2,3,4,5];varsds=arr.map(function(value,index,array){returnvalue*2})console.log(sds)//2, 4, 6, 8, 10 ...
JavaScript 中 Array map() 方法 考察下面的一个实例：const array1 = [1, 4, 9, 16];// pass a function to mapconst map1 = array1.map(x => x * 2);console.log(map1);// expected output: Array [2, 8, 18, 32]在上面的方法中，返回了一个对数组 map 后的结果。方法解读 map() ...