How to Check if String has Text in Javascript
In this tutorial, you will learn how to check if string has text in javascript. A text is just a string which consists of multiple characters such as numbers, letters, or special characters. For a newbie developer, it can be a bit tricky to find if the string has a text.
There are numerous ways to check if a string has a text. But for the sake of simplicity, we will use the includes()
method and ternary operator (?
) to accomplish our goal. The includes()
method is used to perform a case-sensitive search to detect whether a string contains another string or not and returns a Boolean value.
In the following example, we have one global variable that holds a string. Upon click of a button, we will check if it has a text and display the result on the screen. Please have a look over the code example and the steps given below.
HTML & CSS
- We have 3 elements in the HTML file (
div
,button
, andh1
). Thediv
element is just a wrapper for the rest of the elements. - The
innerText
for thebutton
element is“Check”
and for theh1
element, it is“Result”
. - We have done some basic styling using CSS and added the link to our
style.css
stylesheet inside thehead
element. - We have also included our javascript file
script.js
with ascript
tag at the bottom.
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <link rel="stylesheet" href="style.css"> <title>Document</title> </head> <body> <div class="container"> <button>Check</button> <h1>Result</h1> </div> <script src="script.js"></script> </body> </html>
.container { text-align: center; } button { margin-top: 10px; padding: 10px 20px; }
Javascript
- We have selected the
button
element andh1
element using thedocument.querySelector()
method and stored them inbtnCheck
andoutput
variables respectively. - We have attached a
click
event listener to thebutton
element. - We have a global variable
myString
which holds a string as its value. - In the event handler function, we are using the
includes()
method and ternary operator (?
) to verify whethermyString
has the“sky”
text or not. Theincludes()
method will return true if the string has the text. - Depending upon the result of the check, we will assign
“Yes”
or“No”
to theresult
variable. - We are displaying the
result
in theh1
element using theinnerText
property.
let btnCheck = document.querySelector("button"); let output = document.querySelector("h1"); let myString = "The color of the sky is blue."; btnCheck.addEventListener("click", () => { let result = myString.includes("sky") ? "Yes" : "No"; output.innerText = result; });