urlencode

(PHP 4, PHP 5, PHP 7, PHP 8)

urlencode — URL-encodes string

Description

urlencode(string $string): string

This function is convenient when encoding a string to be used in a query part of a URL, as a convenient way to pass variables to the next page.

Parameters

string: The string to be encoded.

Return Values

Returns a string in which all non-alphanumeric characters except -_. have been replaced with a percent (%) sign followed by two hex digits and spaces encoded as plus (+) signs. It is encoded the same way that the posted data from a WWW form is encoded, that is the same way as in application/x-www-form-urlencoded media type. This differs from the » RFC 3986 encoding (see rawurlencode()) in that for historical reasons, spaces are encoded as plus (+) signs.

Examples

Example #1 urlencode() example

<?php
$userinput = 'Data123!@-_ +';
echo "UserInput: $userinput\n";
echo '<a href="mycgi?foo=', urlencode($userinput), '">';
?>

The above example will output:

UserInput: Data123!@-_ +
<a href="mycgi?foo=Data123%21%40-_+%2B">

Example #2 urlencode() and htmlentities() example

<?php
$foo = 'Data123!@-_ +';
$bar = "Not the same content as $foo";
echo "foo: $foo\n";
echo "bar: $bar\n";
$query_string = 'foo=' . urlencode($foo) . '&bar=' . urlencode($bar);
echo '<a href="mycgi?' . htmlentities($query_string) . '">';
?>

The above example will output:

foo: Data123!@-_ +
bar: Not the same content as Data123!@-_ +
<a href="mycgi?foo=Data123%21%40-_+%2B&amp;bar=Not+the+same+content+as+Data123%21%40-_+%2B">

Notes

Note:
Be careful about variables that may match HTML entities. Things like &amp, &copy and &pound are parsed by the browser and the actual entity is used instead of the desired variable name. This is an obvious hassle that the W3C has been telling people about for years. The reference is here: » http://www.w3.org/TR/html4/appendix/notes.html#h-B.2.2.

PHP supports changing the argument separator to the W3C-suggested semi-colon through the arg_separator .ini directive. Unfortunately most user agents do not send form data in this semi-colon separated format. A more portable way around this is to use & instead of & as the separator. You don't need to change PHP's arg_separator for this. Leave it as &, but simply encode your URLs using htmlentities() or htmlspecialchars().

Found A Problem?

Learn How To Improve This Page • Submit a Pull Request • Report a Bug

＋add a note

User Contributed Notes 6 notes

down

davis dot peixoto at gmail dot com ¶

14 years ago

urlencode function and rawurlencode are mostly based on RFC 1738.

However, since 2005 the current RFC in use for URIs standard is RFC 3986.

Here is a function to encode URLs according to RFC 3986.

<?php
function myUrlEncode($string) {
    $entities = array('%21', '%2A', '%27', '%28', '%29', '%3B', '%3A', '%40', '%26', '%3D', '%2B', '%24', '%2C', '%2F', '%3F', '%25', '%23', '%5B', '%5D');
    $replacements = array('!', '*', "'", "(", ")", ";", ":", "@", "&", "=", "+", "$", ",", "/", "?", "%", "#", "[", "]");
    return str_replace($entities, $replacements, urlencode($string));
}
?>

down

temu92 at gmail dot com ¶

15 years ago

I needed encoding and decoding for UTF8 urls, I came up with these very simple fuctions. Hope this helps!

<?php
    function url_encode($string){
        return urlencode(utf8_encode($string));
    }
    
    function url_decode($string){
        return utf8_decode(urldecode($string));
    }
?>

down

materialsmoke at gmail dot com ¶

1 year ago

this function will encode the URL while preserving the functionality of URL so you can copy and paste it in the browser
```
function urlEncode($url) {
    $parsedUrl = parse_url($url);
    
    $encodedScheme = urlencode($parsedUrl['scheme']);
    $encodedHost = urlencode($parsedUrl['host']);
    
    $encodedPath = implode('/', array_map('urlencode', explode('/', $parsedUrl['path'])));
    if (isset($parsedUrl['query'])) {
        $encodedQuery = '?' . urlencode($parsedUrl['query']);
    } else {
        $encodedQuery = '';
    }
    
    return "{$encodedScheme}://{$encodedHost}{$encodedPath}{$encodedQuery}";
}
```

down

daniel+php at danielnorton dot com ¶

15 years ago

Don't use urlencode() or urldecode() if the text includes an email address, as it destroys the "+" character, a perfectly valid email address character.

Unless you're certain that you won't be encoding email addresses AND you need the readability provided by the non-standard "+" usage, instead always use use rawurlencode() or rawurldecode().

down

omid at omidsakhi dot com ¶

14 years ago

I needed a function in PHP to do the same job as the complete escape function in Javascript. It took me some time not to find it. But findaly I decided to write my own code. So just to save time:



<?php

function fullescape($in)

{

  $out = '';

  for ($i=0;$i<strlen($in);$i++)

  {

    $hex = dechex(ord($in[$i]));

    if ($hex=='') 

       $out = $out.urlencode($in[$i]);

    else 

       $out = $out .'%'.((strlen($hex)==1) ? ('0'.strtoupper($hex)):(strtoupper($hex)));

  }

  $out = str_replace('+','%20',$out);

  $out = str_replace('_','%5F',$out);

  $out = str_replace('.','%2E',$out);

  $out = str_replace('-','%2D',$out);

  return $out;

 }

?>



It can be fully decoded using the unscape function in Javascript.

down

ahrensberg at gmail dot com ¶

17 years ago

Like "Benjamin dot Bruno at web dot de" earlier has writen, you can have problems with encode strings with special characters to flash. Benjamin write that:

<?php
   function flash_encode ($input)
   {
      return rawurlencode(utf8_encode($input));
   }
?>

... could do the problem. Unfortunately flash still have problems with read some quotations, but with this one:

<?php
   function flash_encode($string)
   {
      $string = rawurlencode(utf8_encode($string));

      $string = str_replace("%C2%96", "-", $string);
      $string = str_replace("%C2%91", "%27", $string);
      $string = str_replace("%C2%92", "%27", $string);
      $string = str_replace("%C2%82", "%27", $string);
      $string = str_replace("%C2%93", "%22", $string);
      $string = str_replace("%C2%94", "%22", $string);
      $string = str_replace("%C2%84", "%22", $string);
      $string = str_replace("%C2%8B", "%C2%AB", $string);
      $string = str_replace("%C2%9B", "%C2%BB", $string);

      return $string;
   }
?>

... should solve this problem.

＋add a note

urlencode

Description

Parameters

Return Values

Examples

Notes

See Also

Found A Problem?

User Contributed Notes 6 notes