javascript test method

How does RegExp test() Method Works in JavaScript?

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Learn everything you need to know about the test() method of the RegExp object in JavaScript.

This article explains the syntax, parameters, and return value of the test() method, as well as how to use it with examples.

Discover how the test() method works and which browsers support it. Read on to become an expert in using the test() method in JavaScript.

What is test () method in JavaScript?

In JavaScript, the RegExp object has a method called test().

The test() method is used to search for a match between a regular expression and a given string.

If it finds a match, it returns true. If not, it returns false.

This is useful when you want to check if a string contains a specific pattern.

For instance, you can use the test() method to see if a string contains a certain word or character.

Syntax

RegExpObject.test(string) ✅

Parameter 

string

The string to be searched. This parameter is required.

Return value

This method will return true, if it finds a match, otherwise, it returns false.

Browsers that supported by RegExp test() method

✔ Google Chrome

✔ Edge

✔ Mozilla Firefox

✔ IE

✔ Safari

✔ Opera

How to use RegExp.prototype.test()?

Here’s an example of how to use the RegExp.prototype.test() method in JavaScript.

In this example, we search for the occurrence of the string “itsourcecode” within the original string.

const string = "Hi, Welcome to itsourcecode!";
const result = /itsourcecode/.test(string); ✅
console.log(result);

As you can see, our example code uses the test() method of the RegExp object in JS to search for a match between a regular expression and a specified string.

The regular expression /itsourcecode/ is used to search for the string “itsourcecode” within the string string.

If the test() method finds a match, it returns true, otherwise it returns false. In this case, since the string “itsourcecode” does appear within the string:

The test() method returns:

true

In our second example, we search for the occurrence of the string “Hello” within the original string.

const string = "Hi, Welcome to itsourcecode!";
const result = /Hello/.test(string); ✅
console.log(result);

Since the string “Hello” do not appear within the string:

The test() method returns:

false

Moreover, you can also test() method in a function like the following code:

function sample() {
    let string = "Hi, Welcome to Itsourcecode tha offers free sourcecode";
    let regex = new RegExp("Itsourcecode",);
    let rex = regex.test(string); ✅
 
    console.log(rex);
}
sample()

Output:

true

How does test() method works in JavaScript?

The test() method works in JS by executing a search to search for a match between a regular expression and a specified string. If it finds a match, it returns true, otherwise it returns false.

Conclusion

In conclusion, the test() method is a powerful tool for searching for matches between regular expressions and strings in JavaScript.

This article has provided the usage of the test() method, including examples and explanations of how it works.

We are hoping that this article provides you with enough information that help you understand the JavaScript test method.

If you want to dive into more JavaScript topics, check out the following articles:

Thank you for reading Itsourcecoders 😊.

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