stripos Check if a parameter is included in the URL

It is a common requirement to process URLs and their parameters in PHP, especially in scenarios such as jump judgment, record source or security verification. stripos() is a very practical function that can be used to determine whether a string contains another string, and yes.

This article will introduce how to use stripos() to check whether a URL contains specified parameters, such as ref=abc , utm_source , etc.

What is stripos() ?

stripos() is a built-in function of PHP, and its usage is as follows:

 int|false stripos(string $haystack, string $needle, int $offset = 0)

It returns the location where the needle first appears in haystack and false if not found. Unlike strpos() , strpos() is case-insensitive.

Scenario: Detect whether a query parameter is included in the URL

Suppose we have a URL:

 $url = "https://m66.net/shop/product.php?id=123&ref=abc&utm_source=google";

We want to check whether this URL contains the parameter ref=abc .

Sample code:

 <?php

$url = "https://m66.net/shop/product.php?id=123&ref=abc&utm_source=google";

// Parameters to be found
$param = "ref=abc";

// use stripos Do a search
if (stripos($url, $param) !== false) {
    echo "URL Includes parameters '{$param}'。";
} else {
    echo "URL No parameters are included '{$param}'。";
}

Output result:

 URL Includes parameters 'ref=abc'。

Tips and precautions

1. stripos() returns the matching position , not the boolean value, so you need to use !== false to determine whether the match is successful.

2. stripos() is case-insensitive, if you want case-sensitive checks, please use strpos() .

3. If you want to detect multiple parameters, it is recommended to use them in combination with loops, or parse the parameters into an array and then process them.

Advanced example: Detect multiple parameters

 <?php

$url = "https://m66.net/shop/product.php?id=123&ref=abc&utm_source=google";

$params = ["ref=abc", "utm_source=google", "campaign=summer"];

foreach ($params as $param) {
    if (stripos($url, $param) !== false) {
        echo "URL Include parameters：{$param}\n";
    } else {
        echo "URL 不Include parameters：{$param}\n";
    }
}

Summarize

Using stripos() is a simple and quick way to check if there are certain keywords or parameters in the URL. It is a perfect tool when you don't care about case, or just want to do a simple include check.

If you need more rigorous URL parsing (such as extracting parameter values, constructing query strings, etc.), you can consider using functions such as parse_url() and parse_str() .

Hope this article helps you! If you have any further questions, please continue to communicate!