"]// (2) [2, "id3"] https://reactgo.com/javascript-get-index-for-of-loop/ https://stackoverflow.com/questions/10179815/get-loop-counter-index-using-for-of-syntax-in-javascript refs js & for & for of & for in & forEach, break https://www.cnblogs.com/xgqfrms/p/12021774.html ...
In JavaScript, the for loop can be achieved in different ways - for, for...in, for...of, and forEach - which are useful for different case scenarios. for..of allows us to access the element of the array directly without having to use any index value which is typically inserted into...
如果我们想要获取字符串中"for of"循环中字符的位置,可以借助字符串的indexOf()方法来实现。indexOf()方法可以返回指定字符或子字符串在字符串中第一次出现的位置。 以下是一个示例代码: 代码语言:javascript 复制 conststr="Hello for of loop";consttarget="o";for(constcharofstr){if(char===target)...
console.log(index); } 总结 当遍历Array时候,在需要索引时候推荐用forEach,不需要索引时候用for...of...。 当迭代Object时候,虽然只能用for...in...配合hasOwnproperty过滤不需要的,但我还是推荐用Object.keys()配合forEach: Object.keys(obj).forEach(function(key) { ... }); 当迭代String、arguments等...
Often statement 2 is used to evaluate the condition of the initial variable.This is not always the case, JavaScript doesn't care. Statement 2 is also optional.If statement 2 returns true, the loop will start over again, if it returns false, the loop will end....
在JavaScript中,对象的属性分为可枚举和不可枚举之分,它们是由属性的enumerable值决定的。可枚举性决定了这个属性能否被for…in查找遍历到。 像Array和Object使用内置构造函数所创建的对象都会继承自Object.prototype和String.prototype的不可枚举属性,例如 String 的 indexOf() 方法或 Object的toString()方法。循环将遍...
JavaScript for...of loop The syntax of thefor...ofloop is: for(elementofiterable) {// body of for...of} Here, iterable- an iterable object (array, set, strings, etc). element- items in the iterable In plain English, you can read the above code as: for every element in the iter...
问题仍然适用于for…of循环。> 不要使用for…in迭代Array,使用它迭代对象的 _属性_。话说这 我知道 JavaScript 中的基本for…in语法如下所示: for (var obj in myArray) { // ... } 但是我如何获得循环 _计数器/索引_? 我知道我可能会做类似的事情: ...
If it returns false, the loop will end.Note If you omit expression 2, you must provide a break inside the loop. Otherwise the loop will never end. This will crash your browser. Read about breaks in a later chapter of this tutorial....
JavaScript for (var i = 0; i < 5; i++) { console.log(i); } The code is the exact same as before, just that now the loop's body is a block statement containing the console.log() invocation. Moving on, note that the same result of iterating from 0 to 4 could've also been...