How to determine if php is a url

How to use PHP to determine whether it is a URL: 1. Use the regular expression "preg_match($preg,$url)" to achieve the determination; 2. Use the PHP built-in function "filter_var ()" to achieve the determination.

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PHP determines whether the legal string of the URL is URL link

There are many friends who cannot accurately determine whether a string is a standard URL link address when crawling or under other circumstances, which is very troublesome. Let's take a look at how to determine the URL. of legality.

The following codes are all PHP language codes, but the languages ​​​​are all the same.

The first type: regular expression

<?php
function or_url($url){
    $preg = "/http[s]?:\/\/[\w.]+[\w\/]*[\w.]*\??[\w=&\+\%]*/is";
    if(preg_match($preg,$url)){
        echo &#39;正确的 url 地址&#39;;
    }else{
        echo &#39;不是合法的 url 地址&#39;;
    }
}

The second type: using the built-in function filter_var () recommended

<?php
function or_url($url){
    if (filter_var($url, FILTER_VALIDATE_URL) !== false) {
        echo &#39;url 地址正确&#39;;
    }else{
        echo &#39;url 地址不正确&#39;;
    }
}

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