function rollCall(name, index, array) { let nextItem = index + 1 < array.length ? "postive" : "negative" console.log(`Is the number ${index + 1} student - ${name} present? Yes!. Is there a next student? ${nextItem}!`); } names.forEach((name, index, array) => rollCall(...
JavaScript 为我们提供了内置方法 indexOf()。 这个方法让我们可以方便地检查某个元素是否存在于数组中。 indexOf() 方法接受一个元素作为输入参数,并返回该元素在数组中的位置(索引);若该元素不存在于数组中则返回 -1。 AI检测代码解析 function quickCheck(arr, elem) { return arr.indexOf(elem) != -1 ?
(2)只要indexOf 返回的结果不是 -1 就继续往后查找。 (3)因为indexOf 只能查找到第一个,所以后面的查找,可以利用第二个参数,在当前索引加1,从而继续查找。 代码实现: ```js var str = 'qianguyihao'; var index = str.indexOf('a'); var num = 0; while (index !== -1) { console.log(index...
string-in-js npm package The string-in-js npm package provides string manipulation functions designed to enhance JavaScript's built-in string capabilities. It provides a set of intuitive functions that allow you to easily transform and manipulate strings in various ways. Installation To start using...
indexOf()Returns the index (position) of the first occurrence of a value in a string lastIndexOf()Returns the index (position) of the last occurrence of a value in a string lengthReturns the length of a string localeCompare()Compares two strings in the current locale ...
String.prototype.lastIndexOf()从字符串对象中返回最后一个被发现的给定值的索引值,如果没有找到则返回-1。 String.prototype.localeCompare()返回一个数字表示是否引用字符串在排序中位于比较字符串的前面,后面,或者二者相同。 String.prototype.match()使用正则表达式与字符串相比较。 String.prototype.normalize()返回...
This JavaScript tutorial explains how to use the string method called indexOf() with syntax and examples. In JavaScript, indexOf() is a string method that is used to find the location of a substring in a string.
text.indexOf("a"); Try it Yourself » Description TheindexOf()method returns the position of the first occurrence of a value in a string. TheindexOf()method returns -1 if the value is not found. TheindexOf()method is case sensitive. ...
In JavaScript, lastIndexOf() is a string method that is used to find the location of a substring in a string, searching the string backwards. Because the lastIndexOf() method is a method of the String object, it must be invoked through a particular instance of the String class.Syntax...
var word = s.substring(s.indexOf(" ")+1,s.length); console.log(word) 书中给出的答案是:“只要引用了字符串s的属性,Javascript会将字符串转换成对象—new String(s)”。我们知道,转换过程是由V8完成,为了看懂这一转换过程,我将其拆解成以下两个问题进行回答: ...