Introduction to the URL parsing functions parse_url and parse_str in PHP

This article mainly introduces the URL parsing functions parse_url and parse_str in PHP, and provides corresponding examples. it is very practical. if you need it, you can refer to the following two methods in PHP to parse the URL, parse_url and parse_str.

Parse_url
Parse the URL and return its components

Mixed parse_url (string $ url [, int $ component =-1])

This function parses a URL and returns an associated array, which contains various components in the URL.

This function is not used to verify the validity of a given URL, but is used to separate it into the parts listed below. Incomplete URLs are also accepted, and parse_url () tries to parse them correctly as much as possible.

Parameters

The url to be parsed. Invalid characters are replaced.

Component specifies one of PHP_URL_SCHEME, PHP_URL_HOST, PHP_URL_PORT, PHP_URL_USER, PHP_URL_PASS, PHP_URL_PATH, PHP_URL_QUERY, or PHP_URL_FRAGMENT to obtain the string of the specified part in the URL. (Besides PHP_URL_PORT, an integer value is returned ).

Return value

For URLs that are seriously unqualified, parse_url () may return FALSE.

If the component parameter is omitted, an associated array is returned. At present, at least one element is included in the array. Possible keys in the array include:

Scheme-such as http
Host
Port
User
Pass
Path
Query-question mark? After
Fragment-after the hash symbol #
If the component parameter is specified, parse_url () returns a string (or an integer if PHP_URL_PORT is specified) instead of an array. If the specified component in the URL does not exist, NULL is returned.

Instance

The code is as follows:

<? Php
$ Url = 'http: // username: password @ hostname/path? Arg = value # anchor ';
Print_r (parse_url ($ url ));
Echo parse_url ($ url, PHP_URL_PATH );
?>

The above routine will output:

The code is as follows:

Array
(
[Scheme] => http
[Host] => hostname
[User] => username
[Pass] => password
[Path] =>/path
[Query] => arg = value
[Fragment] => anchor
)
/Path

Parse_str

Parses a string into multiple variables.

Void parse_str (string $ str [, array & $ arr])

If str is the query string passed by the URL, it is parsed as a variable and set to the current scope.

Obtain the current QUERY_STRING. you can use the $ _ SERVER ['query _ string'] variable.

Parameters

Str string.

If arr sets the second variable arr, the variable will be saved to this array as an array element, as an alternative. ,

Instance

The code is as follows:

<? Php
$ Str = "first = value & arr [] = foo + bar & arr [] = baz ";
Parse_str ($ str );
Echo $ first; // value
Echo $ arr [0]; // foo bar
Echo $ arr [1]; // baz
Parse_str ($ str, $ output );
Echo $ output ['first']; // value
Echo $ output ['arr'] [0]; // foo bar
Echo $ output ['arr'] [1]; // baz
?>

Some time ago, I was reading the source code of php-resque and saw the application of these two methods. I felt very useful and used to parse the redis link settings.

Redis link format: redis: // user: pass @ host: port/db? Option1 = val1 & option2 = val2, is it the same as the URL, so it is easy to parse with the above two methods.

Address: https://github.com/chrisboulton/php-resque/blob/master/lib/Resque/Redis.php

The code is as follows:

The code is as follows:

/**
* Parse a DSN string, which can have one of the following formats:
*
*-Host: port
*-Redis: // user: pass @ host: port/db? Option1 = val1 & option2 = val2
*-Tcp: // user: pass @ host: port/db? Option1 = val1 & option2 = val2
*
* Note: the 'user' part of the DSN is not used.
*
* @ Param string $ dsn a dsn string
* @ Return array An array of DSN compotnents, with 'false' values for any unknown components. e.g.
* [Host, port, db, user, pass, options]
*/
Public static function parseDsn ($ dsn)
{
If ($ dsn = ''){
// Use a sensible default for an empty DNS string
$ Dsn = 'redis: // '. self: DEFAULT_HOST;
}
$ Parts = parse_url ($ dsn );
// Check the URI scheme
$ ValidSchemes = array ('redis ', 'tcp ');
If (isset ($ parts ['scheme ']) &! In_array ($ parts ['scheme '], $ validSchemes )){
Throw new \ InvalidArgumentException ("Invalid DSN. Supported schemes are". implode (',', $ validSchemes ));
}
// Allow simple 'hostname' format, which 'parse _ url' treats as a path, not host.
If (! Isset ($ parts ['host']) & isset ($ parts ['path']) {
$ Parts ['host'] = $ parts ['path'];
Unset ($ parts ['path']);
}
// Extract the port number as an integer
$ Port = isset ($ parts ['port'])? Intval ($ parts ['port']): self: DEFAULT_PORT;
// Get the database from the 'path' part of the URI
$ Database = false;
If (isset ($ parts ['path']) {
// Strip non-digit chars from path
$ Database = intval (preg_replace ('/[^ 0-9]/', '', $ parts ['path']);
}
// Extract any 'user' and 'pass' values
$ User = isset ($ parts ['user'])? $ Parts ['user']: false;
$ Pass = isset ($ parts ['pass'])? $ Parts ['pass']: false;
// Convert the query string into an associative array
$ Options = array ();
If (isset ($ parts ['query']) {
// Parse the query string into an array
Parse_str ($ parts ['query'], $ options );
}
Return array (
$ Parts ['host'],
$ Port,
$ Database,
$ User,
$ Pass,
$ Options,
);
}

The above is my understanding of the URL functions parse_url and parse_str parsed by php. I will record them here and share them with you. I hope they will help you.