Checking if a URL Contains a Specific String

In web development, it’s often necessary to check if a URL contains a specific string. This can be useful for various purposes, such as redirecting users based on their location, displaying custom content, or triggering certain events. In this tutorial, we’ll explore how to achieve this in JavaScript.

The window.location object provides information about the current URL. However, it’s not a string, so we can’t directly use methods like contains() or indexOf(). Instead, we need to access its href property, which returns the entire URL as a string.

To check if a URL contains a specific string, you can use the indexOf() method, which returns the index of the first occurrence of the specified value. If the value is not found, it returns -1. Here’s an example:

if (window.location.href.indexOf("franky") > -1) {
    alert("Your URL contains the name franky");
}

Alternatively, you can use a regular expression with the test() method:

if (/franky/.test(window.location.href)) {
    alert("Your URL contains the name franky");
}

Note that the indexOf() method is case-sensitive, so if you want to perform a case-insensitive search, you can convert both the URL and the search string to lowercase:

if (window.location.href.toLowerCase().indexOf("franky") > -1) {
    alert("Your URL contains the name franky");
}

Another approach is to use the includes() method, which returns a boolean value indicating whether the string includes the specified value. However, this method is not supported in older browsers, so it’s recommended to use indexOf() for better compatibility:

if (window.location.href.includes("franky")) {
    alert("Your URL contains the name franky");
}

In summary, checking if a URL contains a specific string can be achieved using the indexOf() method or regular expressions. By accessing the href property of the window.location object, you can perform a search and trigger custom actions based on the result.