当一个字符串被传递给一个带有返回语句的函数时,你如何在JavaScript中反转它,而不使用内置函数(.reverse(), . charat()等)?
当前回答
function reverse_string(string)
{
var string;
var len = string.length;
var stringExp = string.split('');
var i;
for (i = len-1; i >=0;i--)
{
var result = document.write(stringExp[i]);
}
return result;
}
reverse_string("This is a reversed string");
//outputs: gnirts描述一个sihT
其他回答
函数反向(字符串) { Let arr = []; For (let char of string) { arr.unshift (char); } Let rev = arr.join(") 返回牧师 } Let result = reverse("hello") console.log(结果)
function reverse_string(string)
{
var string;
var len = string.length;
var stringExp = string.split('');
var i;
for (i = len-1; i >=0;i--)
{
var result = document.write(stringExp[i]);
}
return result;
}
reverse_string("This is a reversed string");
//outputs: gnirts描述一个sihT
这样的事情应该遵循最佳实践:
(function(){ 'use strict'; var str = "testing"; //using array methods var arr = new Array(); arr = str.split(""); arr.reverse(); console.log(arr); //using custom methods var reverseString = function(str){ if(str == null || str == undefined || str.length == 0 ){ return ""; } if(str.length == 1){ return str; } var rev = []; for(var i = 0; i < str.length; i++){ rev[i] = str[str.length - 1 - i]; } return rev; } console.log(reverseString(str)); })();
我自己最初的尝试…
var str = "The Car";
function reverseStr(str) {
var reversed = "";
var len = str.length;
for (var i = 1; i < (len + 1); i++) {
reversed += str[len - i];
}
return reversed;
}
var strReverse = reverseStr(str);
console.log(strReverse);
// "raC ehT"
http://jsbin.com/bujiwo/19/edit?js,console,output
字符串本身是不可变的,但是你可以用下面的代码轻松地创建一个反向副本:
function reverseString(str) {
var strArray = str.split("");
strArray.reverse();
var strReverse = strArray.join("");
return strReverse;
}
reverseString("hello");