NamePros.Com - Check if a URL exists.

NamePros.Com (http://www.namepros.com/)

- CODE (http://www.namepros.com/code/)

- - Check if a URL exists. (http://www.namepros.com/code/315565-check-if-a-url-exists.html)

Check if a URL exists.

Howdy.

This simple function will check if a url is valid (going by parse_url()) and if it's 'online' - by seeing if it returns a 302, 301, or 200 status code.

EDIT: 3/4/2008, updated to more efficient.

PHP Code:

   <?php

 
function is_valid_url($url)

{

    $url = @parse_url($url);

 
    if (!$url)

    {

        return false;

    }

 
    $url = array_map('trim', $url);

    $url['port'] = (!isset($url['port'])) ? 80 : (int)$url['port'];

 
    $path = (isset($url['path'])) ? $url['path'] : '/';

    $path .= (isset($url['query'])) ? "?$url[query]" : '';

 
    if (isset($url['host']) AND $url['host'] != gethostbyname($url['host']))

    {

        if (PHP_VERSION >= 5)

        {

            $headers = implode('', get_headers("$url[scheme]://$url[host]:$url[port]$path"));

        }

        else

        {

            $fp = fsockopen($url['host'], $url['port'], $errno, $errstr, 30);

 
            if (!$fp)

            {

                return false;

            }

            fputs($fp, "HEAD $path HTTP/1.1\r\nHost: $url[host]\r\n\r\n");

            $headers = fread($fp, 4096);

            fclose($fp);

        }

        return (bool)preg_match('#^HTTP/.*\s+[(200|301|302)]+\s#i', $headers);

    }

    return false;

}

 
?>

I needed this a little while ago, and here is what I have:

PHP Code:

    function url_exists($url) {

@ $headers = get_headers($url);

    return preg_match('/^HTTP\/\d\.\d\s+(200|301|302)/', $headers[0]);

}

then use:
if ($headers[0] == 1) {
code
}

Originally Posted by bobby9101

I needed this a little while ago, and here is what I have:

PHP Code:

    function url_exists($url) {

@ $headers = get_headers($url);

    return preg_match('/^HTTP\/\d\.\d\s+(200|301|302)/', $headers[0]);

}

then use:
if ($headers[0] == 1) {
code
}

Not everyone has PHP5 ;)

Updated the code, check first post.

Originally Posted by SecondVersion

Updated the code, check first post.

I don't get it, how to use that code above? sorry, im a newbie with php

Originally Posted by abcde

I don't get it, how to use that code above? sorry, im a newbie with php

First, you need a webhost which supports PHP or to install it on your own PC. But on your own PC you need to also install a webserver and it's a real hassle so it's easier to have a webhost with this.

Then, input this script in to a file called file.php (or whatever_you_want.php) and save and close the file.

Now in SecondVersion's script he created the function called $is_valid_url($url); so what you'll want to do to see if a URL exists: (within the same file that the function is in [or if it's included for that matter])

PHP Code:

   <?php

// Test script. Function created by SecondVersion

function is_valid_url($url)

{

    $url = @parse_url($url);

 
    if (!$url)

    {

        return false;

    }

 
    $url = array_map('trim', $url);

    $url['port'] = (!isset($url['port'])) ? 80 : (int)$url['port'];

 
    $path = (isset($url['path'])) ? $url['path'] : '/';

    $path .= (isset($url['query'])) ? "?$url[query]" : '';

 
    if (isset($url['host']) AND $url['host'] != gethostbyname($url['host']))

    {

        if (PHP_VERSION >= 5)

        {

            $headers = implode('', get_headers("$url[scheme]://$url[host]:$url[port]$path"));

        }

        else

        {

            $fp = fsockopen($url['host'], $url['port'], $errno, $errstr, 30);

 
            if (!$fp)

            {

                return false;

            }

            fputs($fp, "HEAD $path HTTP/1.1\r\nHost: $url[host]\r\n\r\n");

            $headers = fread($fp, 4096);

            fclose($fp);

        }

        return (bool)preg_match('#^HTTP/.*\s+[(200|301|302)]+\s#i', $headers);

    }

    return false;

}

 
if(is_valid_url("http://namepros.com"))

{

    echo("w00t for Namepros.com! It's alive!");

}else{

    echo("Oh no! Where did NamePros go!?! :(");

}

 
?>

-RageD

Thanks for answering that for me, RageD. :tu:

why not just:

$var = file_get_contents($url);
if ($var == TRUE) {
// url is ok
} else {
// url is invalid
}

Originally Posted by itnashvillecom

why not just:

$var = file_get_contents($url);
if ($var == TRUE) {
// url is ok
} else {
// url is invalid
}

What would be the point of getting the URL's content? That'd be useless and inefficient. This function does the same without the burden of gathering content.

Just set max length to 1 to keep from grabbing the whole thing.. Beats using a gigantic function, overkill to me. Much less processing time and lower load.