步骤2: 从后往前查找子字符串 我们使用 JavaScript 提供的lastIndexOf方法,它可以从后往前查找子字符串的位置。代码如下: // 从后往前查找子字符串constindex=targetString.lastIndexOf(searchString);// 输出查找到的索引console.log(`The last occurrence of '${search
// find last occurrence of "m" in strvarresult = str.lastIndexOf(substr); console.log(result); Run Code Output 7 In the above example, we have defined a string namedstr. Thesubstrvariable contains"m"which is a substring of the given string. ThelastIndexOf()method locates the index of...
Finding a String Inside Another StringYou can use the indexOf() method to find a substring or string within another string. This method returns the index or position of the first occurrence of a specified string within a string.ExampleTry this code » let str = "If the facts don't fit...
一、前言 对恶意样本进行反混淆处理可能是一项比较繁琐的任务。为了减少这项任务所花费的时间,研究人员们正不断尝试进行自动化的反混淆处理。在本文中,我们将首先分析脚本中的四种不同混淆类型,并探讨如何在正则表达式的帮助下对其进行反混淆。在这里,我们将逐步分析反混淆过程,并尝试设计对应的反混淆工具。在成功进行...
Find the position of the first occurrence of a text in a string - indexOf() Search for a text in a string and return the text if found - match() Replace characters in a string - replace() Convert string to upper case - toUpperCase() ...
Write a JavaScript function that uses the reduce() method to determine the longest string in an array, returning the first occurrence in case of ties. Write a JavaScript program that compares the lengths of strings in an array and outputs the string with maximum length after validation.Improve...
The lastIndexOf() method returns the position of the first occurrence of substring instringwhen searching thestringbackwards. The first position in thestringis 0. If the lastIndexOf() method does not find thesubstringinstring, it will return -1. ...
arr.filter((v,i,a)=>a.findIndex(t=>(JSON.stringify(t) ===JSON.stringify(v)))===i) Run Code Online (Sandbox Code Playgroud) Keep the last occurrence. Add slice and reverse to beginning and reverse again in the end. arr.slice().reverse().filter((v,i,a)=>a.findIndex(t=>(t...
stringif(typeofstr!=='string'){// Return a message if the input is not a stringreturn'It must be a string.'}// Create a Map to store the occurrences of each character in the stringconstoccurrence_Map=newMap()// Iterate through each character in the stringfor(constcharofstr){// ...
// _.findLastIndex(array, predicate, [context]) _.findLastIndex = createPredicateIndexFinder(-1); 接下来看 _.sortIndex 方法,这个方法无论使用还是实现都非常的简单。如果往一个有序数组中插入元素,使得数组继续保持有序,那么这个插入位置是?这就是这个方法的作用,有序,很显然用二分查找即可。不多说,...