If you don’t wish to use includes you can go with good old indexOf method. 'hello javascript'.indexOf('javascript') !== -1 // output: true indexOf will return starting index of the substring, if it is found. If the substring is missing from string, it’ll return -1. ...
To check if a variable is a string in JavaScript, use thetypeofoperator, e.g.typeof a === 'string'. If thetypeofoperator returns"string", then the variable is a string. For all other values, the variable is not a string. letname='Atta'if(typeofname==='string'){console.log(`Va...
JavaScript offers many ways to check if a string contains a substring. Learn the canonical way, and also find out all the options you have, using plain JavaScriptChecking if a string contains a substring is one of the most common tasks in any programming language....
Another method to check if a string is a palindrome or not is by using aforloop. Below are the steps to check if a string is a palindrome in JavaScript. functionpalindromeFn(string){conststringLength=string.length;for(leti=0;i<stringLength/2;i++){if(string[i]!==string[stringLength-1...
In this tutorial, we are going to show you the ways of checking whether the JavaScript string is empty, undefined, or null. Just follow the guidelines.
String.includes() Method The String.includes()provides the most simple and popular way to check if a string contains a substring in modern JavaScript. It was introduced in ES6 and works in all modern browsers except Internet Explorer. The String.includes() method returns true if the string con...
if(typeofmyVar==="string"){console.log("myVar is a string");}else{console.log("myVar is not a string");} Another way to check if a variable is a string is to use theinstanceofoperator, which returns true if an object is an instance of a particular constructor. For example, the ...
To check if a string is url, we can use the following regex pattern in JavaScript. Here is an example: function isURL(str) { const pattern = new RegExp('^(https?:\\/\\/)?'+ // protocol '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|'+ // domain name...
That’s all about parsing a string in JavaScript. Conclusion To parse a string in JavaScript, use “parseInt()”, “parseFloat()”“Date.parse()” or the “JSON.parse()” methods. These methods parse the string into an integer, floating point number, Date object, and Object. This article...
Method 2: Check if String Does Not Contain Letters Using match() Method The “match()” method in JavaScript is also used to determine whether a string contains letters or not. A string is compared to a regular expression or regex pattern using the match() method. It returns an array of...