I have this string in PHP:
$string = "name=Shake & Bake&difficulty=easy";
For which I want to parse into array:
Array
(
[name] => Shake & Bake
[difficulty] => easy
)
NOT:
Array
(
[name] => Shake
[difficulty] => easy
)
What is the most efficient way to do this ?
Regular expressions seems to be the best way to do this.
<html>
<head>
<title>Test params</title>
</head>
<body>
<?php
test_build('a=b');
test_build('blah=foo&foo=foo2');
test_build('blah=foo&foo&foo2=foo3&foo');
function test_build($string) {
echo "<p>Testing: $string</p>\n";
$params = build_params($string);
if ($params) {
echo "<ul>\n";
foreach ($params as $k => $v) {
echo "<li>'$k' => '$v'</li>\n";
}
echo "</ul>\n";
} else {
echo "<p>Found no parameters.</p>\n";
}
}
function build_params($string) {
preg_match_all('!([^=&]+)=([^=]*)(?=(&|$))!', $string, $matches);
$ret = array();
for ($i=0; $i<sizeof($matches[1]); $i++) {
$ret[$matches[1][$i]] = $matches[2][$i];
}
return $ret;
}
?>
</body>
</html>
Output:
Testing: a=b
* 'a' => 'b'
Testing: blah=foo&foo=foo2
* 'blah' => 'foo'
* 'foo' => 'foo2'
Testing: blah=foo&foo&foo2=foo3&foo
* 'blah' => 'foo&foo'
* 'foo2' => 'foo3&foo'
There's probably a more effective way of doing this, but try
$foo = 'name=Shake & Bake&difficulty=easy';
$pairs = preg_split('{&(?=[^\s])}',$foo);
//$pairs = preg_split('/&(?=[^\s])/',$foo); //equivalent, using different delimiters.
//$pairs = preg_split('%&(?=[^\s])%',$foo); //equivalent, using different delimiters.
$done = Array();
foreach($pairs as $keyvalue){
$parts = preg_split('{=}',$keyvalue);
$done[$parts[0]] = $parts[1];
}
print_r($done);
PHP's regex engine is PCRE, and it supports look ahead assertions. Googling around for PCRE, PHP, RegEx, look ahead assertions and zero width assertions should give you more than you ever want to know on the subject.
The function parse_str() does exactly what you need - just make sure, you pass the second parameter for obvious security reasons. You need to translate your input string, though:
$string = "name=Shake & Bake&difficulty=easy";
parse_str(str_replace(' & ', '+%26+', $string), $array);
<?php $pattern ='/([^&]+)=([^=]+)(?=$|&[^=]+=)/';produces
$test = array( 'name=Shake & Bake&difficulty=easy', 'name=Shake&Bake&difficulty=easy', 'difficulty=easy&name=Shake & Bake', 'difficulty=easy&name=Shake&Bake', 'name=Shake&Bake', 'difficulty=easy', 'name=Shake&Bake&foo&difficulty=easy', 'name=Shake&Bake&difficulty=easy&', 'name=Shake&Bake&difficulty=' ); foreach($test as $foo) { preg_match_all($pattern, $foo, $m); echo $foo, "\n"; for($i=0; $i<count($m[0]); $i++) { echo ' ', $m[1][$i], ' =$gt; "', $m[2][$i], "\"\n"; } echo "\n"; } ?>
name=Shake & Bake&difficulty=easy name => "Shake & Bake" difficulty => "easy"which seems to be working (except for difficulty= not being matched in the last example).
name=Shake&Bake&difficulty=easy name => "Shake&Bake" difficulty => "easy"
difficulty=easy&name=Shake & Bake difficulty => "easy" name => "Shake & Bake"
difficulty=easy&name=Shake&Bake difficulty => "easy" name => "Shake&Bake"
name=Shake&Bake name => "Shake&Bake"
difficulty=easy difficulty => "easy"
name=Shake&Bake&foo&difficulty=easy name => "Shake&Bake&foo" difficulty => "easy"
name=Shake&Bake&difficulty=easy& name => "Shake&Bake" difficulty => "easy&"
name=Shake&Bake&difficulty= name => "Shake&Bake"