Javascript string contains substring To check if a string contains substring or not, use the Javascript match method. [GFGTABS] JavaScript const a = Sep 22, 2022 · When you’re testing if a string contains a specific substring, you might be inclined to use a method like indexOf(). indexOf('foo') >= 0; // true The indexOf method returns the character index where the first occurrence of the specified value is encountered, if not found, it returns -1 . Jun 14, 2016 · I have a string containing a person's first and last name such as John Doe. includes(searchTerm); // true. It works like this: > let str = 'stackabuse'; > let substr = 'stack'; > str. findIndex() method to iterate over the array. match method of the argument with the string as the first parameter. Dec 3, 2024 · Here are the different ways to check if an array of strings contains a substring in JavaScript 1. match](). (ES6) includes - aller à la réponse var string = "foo", substring = "oo"; string. It is often used in arrays, and the same can be applied with strings. Let's have a look at how to check if a string contains a substring in JavaScript. Unfortunately, JavaScript's built-in tools for doing so leave quite a bit to be desired. The actual implementation comes from RegExp. I would like to convert this string to John D. Jan 2, 2025 · H ere are the different ways to check if an array of strings contains a substring in JavaScript. Dec 2, 2024 · Here are the different methods to check whether a string contains a substring in JavaScript. includes(); ES6 contains inbuilt method (includes) in String's prototype, which can be used to check if string contains another string or not. If the expression and the string match it results in true and returns token ( which is the string the switch statement is operating on ). Mar 3, 2025 · In JavaScript, checking whether a string contains a specific substring is a common task. Instead, try RegExp. Cómo usar el método indexOf() de JavaScript. How to check whether a string contains a substring in JavaScript? By using the following methods, you can easily check whether a string contains a substring in JavaScript: Sep 15, 2023 · In this article, we will discuss the JavaScript Test if String Contains Substring. [GFGTABS] JavaScript const a = Apr 24, 2019 · There are multiple ways to check if a string contains a substring in JavaScript. To check if a string contains substring JavaScript, we commonly refer to the includes() method because of its targeted design towards a string and the letters search. Here's an example: Feb 15, 2011 · What is the regex for simply checking if a string contains a certain word (e. includes(sub_str) if result{ * Stuff todo if result found }else{ * Stuff todo if result not found } result true; // if you have sub string finder method separately and calling it from The substring() method extracts characters, between two indices (positions), from a string, and returns the substring. If the string does not contain the substring, indexOf() returns -1. Oct 21, 2022 · The code above returns 8. The includes() method is arguably the most common way of checking if a string contains a substring. It returns the index of the first occurrence of the specified substring within the string, or -1 if the substring is not found. in ITSM forum 2 weeks ago Applying complex Query in ITSM forum 2 weeks ago Using Image Variable Type to Put In Image Into Knowledge Base Article in ITSM forum 2 weeks ago May 25, 2023 · In this article, we'll explore different approaches to check whether a string contains a substring in JavaScript. Checking whether a string contains a specific substring is a common task in JavaScript. If the string contains the substring, indexOf() returns the index of the first occurrence of the substring. Jan 10, 2025 · The String constructor property in JavaScript is used to return the string constructor function for the object. Here's an example of how to use the includes() method:. This operation is useful for various applications, such as searching for keywords in user input, filtering data, or validating form inputs. As you can see, a boolean value is returned since the string "stack" is a substring of stackabuse. After that, we discussed three ways in which you can check if a string contains a substring in JavaScript: using includes(), indexOf(), and regex. includes("#") May 16, 2024 · The indexOf method in JavaScript is a simple and efficient way to check if a string contains a substring. indexOf("the"); // position = 5 If the given string isn't present, indexOf will return -1. Dec 2, 2024 · Here are the different ways to check if an array of strings contains a substring in JavaScript 1. Summary: in this tutorial, you will learn how to use the JavaScript String includes() method to check if a string contains a substring. Javascript string substring check May 25, 2024 · Check if a string contains a substring in JavaScript. Introduction to JavaScript String includes() method The includes() method performs a case-sensitive search and determines if a substring is included in a string: Oct 24, 2010 · /** Function that count occurrences of a substring in a string; * @param {String} string The string * @param {String} subString The sub string to search for * @param {Boolean} [allowOverlapping] Optional. So if the search is larger or equal to 0, the substring exist. Using regex for a task like this gives you a lot more flexibility than with the previous methods where you can only check for a constant string. include() that we have covered so far, String. var a = 'good morning'; Here are the different ways to check if string contains substring in JavaScript. JavaScript Program to Check Whether a String Contains a Substring. The first parameter is the substring to search for, and the second optional parameter is the Feb 13, 2024 · Hi @gunishi ,. If there is a substring it returns the index it was found (some number from 0 to n), otherwise if it's not found it returns -1. contains(text, Dec 21, 2016 · I looks like your if logic here was if the first name doesn't contain "stream" or name 1 and 2 do not contain stream but your checking name 1 with lowercase "stream" and name 2 with uppercase "stream". match doesn't do much other than calling the Symbol. We will see the built-in May 22, 2015 · You don't really need jQuery for such a simple thing, you can simply use the indexOf method of String objects, e. includes(substring); 2. Jan 26, 2010 · Javascript seems to use locale "C" for string comparisons so the resulting ordering will be ugly if the strings contain other than ASCII letters. includes(term, start) method, which checks if the string contains the substring. The following shows you different ways of finding a substring in a JavaScript string: Using String. This option is essential if you want to replace all occurances of the search string (which is usually what you want). prototype's indexOf method. Jan 21, 2025 · The ‘includes()’ method is a simple and straightforward way to check if a string contains a specific substring. The includes() method is the most simple and modern way to check if a string contains a specific substring. If the separator is omitted, the returned array will contain the whole string in index [0]. The includes method is a powerful tool for this purpose, allowing People here are making this waaay too difficult. The 'every' method executes the provided callback function once for each element present in the array until it finds one where callback returns a falsy value (a value that becomes false when converted to a Boolean). Mar 13, 2025 · The includes() method of String values performs a case-sensitive search to determine whether a given string may be found within this string, returning true or false as appropriate. This method returns a boolean value indicating whether the target string contains the specified substring. indexOf(substring) !== -1); // true Aug 26, 2019 · If we look at the docs for String. Using includes() You can use includes() function to check if a string contains a substring or not. Remove duplicates from the string variable type. g. var string = "foo"; var substring = "oo"; console. Learn how to use the includes() method to check if a string contains a specified string. The first parameter is the string to search for, and the second optional parameter specifies the position from which to search. Dec 8, 2021 · Hi, in this tutorial, we are going to talk about 7 Ways to check if a string contains a substring or not in javascript. : var str = "foobar"; var containsFoo = str. May 25, 2016 · For reducing the function you can use every() and indexOf() methods. Normally, I would just use substring(0,1) on the last name variable, but how can I achieve this when the first and last name are one string with a space in between? Sep 16, 2010 · @EscapeNetscape: Nice to see a benchmark link. indexOf() and String. Topic: JavaScript / jQuery Prev|Next. Using includes() Method. 1. count = 12 Jan 8, 2018 · Need to loop an array of strings and check against with another string, which is passed in the string. Jun 24, 2024 · Learn the best methods to check if a string contains a substring in JavaScript. Mar 31, 2025 · Check Whether String Contains Substring. We will create an array of strings, then use includes() and filter() methods to check whether the array elements contain a sub-string. This method returns true if the substring is found in the string, and false otherwise. Sep 6, 2023 · One of the more useful and powerful ways to check for a substring is to use regular expressions, or regex. This method returns the index or position of the first occurrence of substring within Syntax string. Let's discuss one of the most common tasks bellow. May 2, 2023 · Another way is to use the string indexOf() method, which returns the index of the first occurrence of the substring. May 10, 2020 · JavaScript str. Dec 6, 2022 · It is true that the string JavaScript string contains is easy contains the string substring. includes which accepts a substring as an argument and will return a Nov 8, 2018 · Ask questions, find answers and collaborate at work with Stack Overflow for Teams. Sep 8, 2019 · To check if a string contains a substring using String. Whether you need case-sensitive checks or prefer a flexible, case-insensitive approach, this guide has it covered. Feb 12, 2016 · To check the substring within the string you can use includes jQuery function like this var sub_str = "find" var main_str = "find me if you can" result = main_str. And, it should return true for "keep it on the table". This built-in function on the String object checks if a string contains a substring. In script, you can check if a string contains a specific substring using the indexOf() method or a regular expression. To understand this example, you should have the knowledge of the following JavaScript programming topics: JavaScript String; Javascript String includes() JavaScript String indexOf() Oct 2, 2012 · In the first alert(), JavaScript returned "-1" - in other words, indexOf() did not find a match: this is simply because "JavaScript" is in lowercase in the first string, and properly capitalized in the second. If the string does not contain the given substring, it returns -1. To use the ‘includes()’ method in JavaScript, you can simply call it on a string object with the substring as an argument. Apr 29, 2020 · I need to test whether the innerText of a element contains a substring using testcafe, but I'm not able to figure out the right way to do that. Understanding JavaScript String Basics Aug 16, 2014 · Note that there are plenty of methods that allow you to do this. Unlike String. I tried array. replace() is regexp-based; if you pass in a string as the first argument, the regexp made from it will not include the ‘g’ (global) flag. However, there are two other ways to search if a string contains a specified character or a phrase. Answer: Use the indexOf() Method. String. The includes() method is a simple and straightforward way to check if a string contains a substring. substring case iterates over a potentially much smaller string. indexOf() method on the given string, passing it to the substring as a parameter. Selector('. Just do the following myArray. May 16, 2019 · There's two common ways to check whether a string contains a substring in JavaScript. First of all, let's take a look at using String. Here's an example that demonstrates the usage of the includes() method: Aug 18, 2015 · You can then check for the presence of a string by using indexOf like so: var position = "Find the string". Mar 21, 2022 · The best way one can check if a string contains a substring is to utilize the includes() method. indexOf() method, str. there's not much that can be done about that without doing much more detailed inspection of the strings. Use a regular expression to check if a string contains only alpha or alphanumeric characters in JavaScript. See examples, syntax, parameters, return value and browser support for this ECMAScript6 feature. Checking whether a string contains another string or not is very common in JavaScript and as well as in other programming languages. I am kind of stuck on how to set it so that if I get three "True", I want to execute something, other I want it to do something else. includes() method on the string. it looks like you just want both names not to contain stream, this can be much more easily performed like this. Try Teams for free Explore Teams Apr 14, 2022 · 在本指南中，我们将学习如何使用includes() 方法来查找字符串中的子串；但首先，让我们讨论JavaScript中includes() 的语法。 语法。 string_name. includes() Method. includes(substr); true. Example. lastIndexOf is likely faster - otherwise . However, for more flexible testing and conditions, using regular expressions Jan 7, 2021 · In this tutorial, we discussed the basics of strings in JavaScript. Jun 8, 2017 · I have an array like this: array = ["123", "456", "#123"] I want to find the element which contains the substring "#". '; console. Nov 7, 2024 · JavaScript offers several methods to check whether a string contains a specific substring. var position = "Find the string". Mar 1, 2024 · # Check if a String contains a Substring with String. match() seems to check whether part of a string mat Jun 18, 2016 · Just wondering, is there a way to add multiple conditions to a . How to check if one string contains substring. It's a simple method that returns a boolean value depending on whether the string contains the substring or not. findIndex(element => element. Feb 19, 2023 · Learn 4 approaches to check if a string contains a substring in JavaScript, using regular expression, includes(), indexOf() and a for loop. The JavaScript number constructor, string constructor, Aug 14, 2016 · When working with JavaScript, determining whether a string contains a specific substring is a common task. Apr 10, 2025 · Strings are useful for holding data that can be represented in text form. search(searchValue) searchValue is a regular expression or a string (will be converted to a regular expression). lastIndexOf on a long string that's going to return false is going to iterate over the entire string (O(N)), whereas the . Also, since you only want to match a sub-string, you'll need to remove the start and end anchors ^ and $. indexOf() method. Depending on your needs, choose includes() for a straightforward, case-sensitive check, indexOf() to possibly retrieve the substring's position, or regular expressions for more complex matching requirements. You can try to run the following code to check whether the string “Tutorialspoint: Free Video Tutorial” contains a substring “point” in or not. JavaScript String substring() substring() is similar to slice(). Conditionally check if the returned value is not equal to -1. You can also include the position at which to begin searching the string for the substring. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more. indexOf() to Check if a String Contains Substring in JavaScript This tutorial teaches how to check if a string contains a substring in JavaScript. Javascript match method accepts a regular expression as a parameter and if the string contains the given substring it will return an object with details of index, substring, input, and groups. If start is greater than end, arguments are swapped: (4, 1) = (1, 4). org Nov 16, 2024 · Learn how to use includes(), indexOf() and regular expressions to check if one string is substring of another in JavaScript. . includes()provides the most simple and popular way to check if a string contains a Apr 7, 2011 · Pretty straight forward. 'Test')? dedicated "substring" methods tend to be faster in this case, because it Feb 2, 2024 · Use String. ¿Qué es el método includes() de JavaScript? Veamos su sintaxis. Whether you're building a web application, processing data, or just playing around with code, you may need to check if a string contains a specific substring. findIndex. Sep 9, 2019 · To check if a string contains a substring in JavaScript: Call the String. includes method, for example: var value = str. log(string. It takes a substring as an argument and returns a boolean value, which is exactly what we need. indexOf(), String. The method searches the string for the substring in question and returns the index of the first occurrence if there is one. log(str. includes("substring")) findIndex() is an ES6 higher order method that iterates through the elements of an array and returns the index of the first element that matches some criteria (provided as a function). It returns a Boolean value indicating whether the substring is found within the string. Dec 21, 2023 · Cómo usar el método includes() de JavaScript. Jan 19, 2023 · Si vous utilisez un navigateur moderne ou une version avancée de node, on peut utiliser la méthode ES6 includes(). replace('-',''); Output: -----check Jquery removes first '-' from my text. test(). includes() to Check if a String Contains Substring in JavaScript Use String. match(/spo/) which states the match the string held in token against the regex expression /spo/ ( which is the literal string spo in this case ). But not working for me var str='------check'; str. includes (element, starting_point) 在JavaScript中include()方法需要两个参数。 substring/element。第一个 Methods To Check for JavaScript String Contains. Nov 24, 2009 · Learn how to check whether a string contains a substring in JavaScript using various methods, such as includes, indexOf, or KMP algorithm. Several methods are used to check if a string contains another substring in Javascript. La méthode includes() renvoie true si la sous-chaîne se trouve dans la chaîne de caractères qu’on teste. ES5 et plus indexOf Feb 20, 2024 · Here are the different ways to check if an array of strings contains a substring in JavaScript 1. includes() The most straightforward substring search option is String. innerText = '12 results' Selector('user-details'). The String. Aug 18, 2021 · To check if a string contains a substring in JavaScript the easiest way is to use String. I'm interested in finding if a string contains a word. 3586. The indexOf method would return -1 if the substring is not present in the string. Checking if a string contains a substring is one of the most common tasks in any programming language. Other search methods you can consider include: May 30, 2024 · JavaScript is an incredibly versatile language, and working with strings is one of its many strengths. includes() Mar 26, 2025 · There are subtle differences between the substring() and substr() methods, so you should be careful not to get them confused. includes() str. If you expect majority successes or only small inputs, . substr()'s start index will wrap to the end of the string if it is negative, while substring() will clamp it to 0. Jul 27, 2022 · JavaScript ; String ; String contains substring ; Check if a string contains a substring in JavaScript String. For example, if I apply a search for "on" for the string, "phones are good", it should return false. Using includes() method. includes() we can see it takes a string, not a regular expression. search() accepts a regular expression as its parameter. search(substring) to check if a string contains your substring. Follow our guide for simple and effective solutions. If I change the observation string to a very long UTF-8 multibyte text, the results change drastically? Also, the results changed with change in position of substring in the observation string. # Ignoring case Check if Array contains String - Array. [GFGTABS] JavaScript const a = Mar 1, 2024 · We just need the strings to be in the same case to be able to determine if the substring is contained in the string. substring also risks Voici une liste des possibilités actuelles: 1. The indexOf() method is case-sensitive and accepts two parameters. indexOf() This is a three-step process: Call the indexOf method on the string, passing it the substring as a parameter. The simplest and fastest way to check whether a string contains a substring or not in JavaScript is the indexOf() method. includes() method. match(), regular expressions, or 3rd-party library like Lodash. Jun 9, 2016 · I have multiple sub-strings that I want to find in a single string and if all three are found then do this, if not, do something else. Some of the most-used operations on strings are to check their length, to build and concatenate them using the + and += string operators, checking for the existence or location of substrings with the indexOf() method, or extracting substrings with the substring() method. See examples, explanations, and code snippets from the Stack Overflow community. You can use the includes() method which will return the boolean value whether the substring is present in string or not. See examples, code snippets and FAQs on this topic. Compare the returned value to -1 . var str = 'To be, or not to be, that is the question. includes(), introduced in ES6. search(), String. Using includes() and filter() method. Mar 14, 2019 · So, you can easily check if a string contains a particular substring using the . Oct 27, 2022 · 原文： How to Check if a String Contains a Substring in JavaScript. If the string does not contain the substring then it will return null. The default position is 0. As you can see, the basic syntax allows you to easily check if a string contains a substring in JavaScript. includes("hello", "hi", "howdy"); Imagine the comma states "or". In javascript, I need to check if a string contains any substrings held in an array. search() method. Nov 6, 2021 · indexOf can be used to decide if the string, contains a substring or not. indexOf("notFound"); // position = -1 You can then use this in an if statement like so Sep 6, 2023 · If all you need to do is get a boolean value indicating if the substring is in another string, then this is what you'll want to use. Jun 10, 2022 · Through this tutorial, you will learn how to check whether a string contains a character or substrings in javascript using the javaScript include(), indexOf() method. The two parameters of substr() are start and length, while for substring(), they are start and end. These are: indexOf() method @ANeves But . Aug 25, 2023 · One of the simplest and most straightforward ways to check if a string contains a substring in JavaScript is by using the includes() method. substring is likely faster. According to npm trends, the popular string-includes substring search package receives over 2 million downloads per week in frameworks like React, Vue and Angular. The more modern way is the String#includes() function. includes(), String. If the returned value is not equal to -1, the string contains the substring. Learn the canonical way, and also find out all the options you have, using plain JavaScript. Check String contains substring 1. JavaScript offers different ways to perform this operation. includes() in JavaScript: Call the String. See examples, syntax and pros and cons of each method. Works perfectly fine when search term is a variable. The substring() method does not change the original string. How to check whether a string contains a substring in JavaScript? 3627. How to Check Whether a String Contains a Substring in JavaScript. You can use either String. W3Schools offers free online tutorials, references and exercises in all the major languages of the web. For example you can use string. Here's how you can do it: Using indexOf(): You can use the indexOf() method to check if a string contains a specific substring. Apr 11, 2025 · This method takes two parameters – the substring that you want to search for, and an optional parameter that specifies the starting point of the search. Checks if str contains "world", which it does so returns true. May 1, 2018 · JavaScript offers many ways to check if a string contains a substring. May 20, 2022 · String. 在编写 JavaScript 程序时，你可能需要检查一个字符串是否包含一个子字符串。子字符串是另一个字符串中的字符串。 具体来说，你可能需要检查一个单词是否包含特定字符或特定字符集。 Aug 24, 2024 · Here substring searches help analyze whether strings contain relevant keywords, conventions or formats. Let us say you have the following string. displayed-result'). . let searchTerm = "world"; let str = "Hello world!"; str. May 4, 2016 · Is there a way in lodash to check if a strings contains one of the values from an array? For example: var text = 'this is some sample text'; var values = ['sample', 'anything']; _. The substring() method extracts characters from start to end (exclusive). includes (substring, starting_point) array_name. El método includes() de JavaScript se introdujo con ES6 y la forma más común y moderna de verificar si una cadena contiene un caracter específico o una serie de caracteres. How to check if a string contains a substring in Bash. To do a case insensitive check if an array contains a string: Use the Array. Using the includes() method. It returns true if the substring is found within the string, and false otherwise. includes('To be')); One of the most basic tasks in any programming language is determining whether a string contains a given substring. Using includes() and filter() methodWe will create an array of strings, then use includes() and filter() methods to check whether the array elements contain a sub-string. JavaScript May 8, 2023 · Photo by Markus Spiske on Unsplash. Jan 9, 2023 · I want to use JavaScript (I can also use jQuery) to do check whether a string matches the regex ^([a-z0-9]{5,})$, and get a true or false result. The function which is returned by this property is just the reference to this function, not a string containing the function's name. Example 2: With variable substring. prototype[Symbol. It is a simple and common task, but different languages handle it in different ways. search() is another method that you can use to check if a string contains another word, substring or character inside the main string. includes(substr) . Oct 18, 2022 · Another way to check if a string contains a substring in JavaScript is to use the string. Example-2: Using a substring and a starting position We can also check whether the target substring is located at a specific index. Whether you are a beginner or an experienced developer, this article will provide you valuable understanding into testing strings for substrings. I need to remove One of the most basic tasks in any programming language is determining whether a string contains a given substring. (More on regex anchors) Your code becomes: Mar 13, 2025 · The implementation of String. If the substring isn’t contained in the string, the method will return -1. JavaScript · March 24, 2024 Check if a JavaScript string contains only alpha or alphanumeric characters. var filterstrings = ['firststring','secondstring','thridstring']; var passedinstring = localSt Jul 27, 2011 · To replace substring. Jan 24, 2023 · Checking if String Contains a Substring in JavaScript To check if a string contains a substring in JavaScript, use the string. Pass the substring as a parameter, e. May 24, 2010 · The test in this case is token. See full list on freecodecamp. prototype. hwb zvze bpsc wanxlbw stz lgbz kvxju omrulm qbolcgm dza vtmgl vxk tyji abjdds niuacu