js的数组拼接方法 方法一:concat方法拼接(返回一个新数组) var a1 = [1,2,3,4,5]; var a2 = [‘a’,’b’,’c’]; var newa = a1.concat(...a2); 结果类型:object concat方法:用于连接两个或多个数组,生成新数组,concat后面的数组时操作的时候数组的元素,而不是数组 方法二:join方法拼接(返回...
arr.toString(); // '1,2,3' // join let arr=['1','2','3']; arr.join(','); // '1,2,3' // sort [2, 1, 3].sort(), // [1, 2, 3] [2, 1, 3].sort((a, b) => a < b), // [3, 2, 1] ['a', 'c', 'b'].sort(), // ['a', 'b', 'c'] ['...
文章目录前言循环比较toStringjoinJSON.stringify当数组元素是空元素、null、undefined时null 和 undefined空元素总结 前言在JavaScript中,数组本质上是一种特殊的对象,它的类型值会返回 object。 如果我们需要比较两个数组是否相等,不能像比较基本类型(String、Number、Boolean等)一样,使用 === (或 ==) 来判断 ...
...定义和用法: join() 方法将数组作为字符串返回。...concat() 方法连接字符串 定义和用法: concat() 方法用于连接两个或多个字符串。...该方法没有改变原有字符串,但是会返回连接两个或多个字符串新字符串。 注释:concat() 方法不会修改原字符串的值,与数组的 concat() 方法操作相似。
On the other hand, equality check for complex types likeobjects,arraysandfunctionsis completely different. Two objects are the same if they have the same reference (pointing to the same object in memory). constobj1 = {prop: ’someValue’ };constobj2 = {prop: ’someValue’ };console.log...
if (++j>=elements[i].length) break jloop; continue yloop; } } } } } for (let y = 0; y < grid.length; y++) { console.log(grid[y].join("")); } 像这样的,对吧? 本文支持英文版本,如需查看请点击这里! (查看英文版本获取更加准确信息)...
Old Data Space: Contains only raw data like strings, boxed numbers and arrays of unboxed doubles. Objects that have survived GC in the New Space for long enough are moved here as well. Large Object Space: Objects which are too big to fit in other spaces are created in this space. Each...
const args=Array.prototype.slice.call(arguments);returnargs.join(''); }//goodfunctionconcatenateAll(...args) {returnargs.join(''); } 6.4、使用默认参数语法,而不是对函数参数进行修正,并且应当将函数的默认值参数放在函数的最后 //really badfunctionhandleThings(opts) {//我们不能修改函数的参数//如...
join(''); }); function createFolders(parent, recursion) { if (recursion === 0) return; for (var i = 0; i < 3; i++) { var folder = new Folder(parent, i + ''); parent.children.push(folder); createFolders(folder, recursion - 1); } } createFolders(state.root, 2); // 3...
split('').reverse().join('')); //remove space, reverse, and check }For example:console.log(isPalindrome("level")); // logs 'true' console.log(isPalindrome("levels")); // logs 'false' console.log(isPalindrome("A car, a man, a maraca")); // logs 'true'...