ConFoo 2025

urlencode

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

urlencode编码 URL 字符串

说明

urlencode(string $string): string

此函数便于将字符串编码并将其用于 URL 的请求部分,同时它还便于将变量传递给下一页。

参数

string

要编码的字符串。

返回值

返回字符串,此字符串中除了 -_. 之外的所有非字母数字字符都将被替换成百分号(%)后跟两位十六进制数,空格则编码为加号(+)。此编码与 WWW 表单 POST 数据的编码方式是一样的,同时与 application/x-www-form-urlencoded 的媒体类型编码方式一样。由于历史原因,此编码在将空格编码为加号(+)方面与 » RFC3986 编码(参见 rawurlencode())不同。

示例

示例 #1 urlencode() 例子

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

以上示例会输出:

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

示例 #2 urlencode()htmlentities() 例子

<?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) . '">';
?>

以上示例会输出:

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">

注释

注意:

注意:小心与 HTML 实体相匹配的变量。像 &amp、&copy 和 &pound 都将被浏览器解析,并使用实际实体替代所期待的变量名。这是明显的混乱,W3C 已经告诫人们好几年了。参考地址:» http://www.w3.org/TR/html4/appendix/notes.html#h-B.2.2

PHP 通过 arg_separator.ini 指令,支持将参数分割符变成 W3C 所建议的分号。不幸的是大多数用户代理并不发送分号分隔符格式的表单数据。较为简单的解决办法是使用 &amp; 代替 & 作为分隔符。你不需要为此修改 PHP 的 arg_separator。让它仍为 &,而仅使用 htmlentities()htmlspecialchars() 对你的 URL 进行编码。

参见

添加备注

用户贡献的备注 6 notes

up
66
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));
}
?>
up
9
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));
}
?>
up
1
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}";
}
```
up
8
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().
up
8
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.
up
1
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.
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