PHP : simple string to array

问题

I have strings like var=test;path=test.html

I want to convert these kind of strings like the array printed below :

Array
{
    var  => test
    path => test.html,
}

I tried to use PHP's explode function for this task, but this is converting the string to associative array, and then i decided to convert that associate array to the one shown above.

But my own code isn't what i'm looking for, 'cause it contain 2 times PHP's explode function and some foreach loops, thus my own code will not stand in the department of performance for such a simple task.

Your help will be much appreciated, thanks.

回答1:

You could use preg_match_all to get an array of keys, and an array of values, then combine them into an associative array using array_combine:

$str = "var=test;path=test.html";
preg_match_all("/([^;=]+)=([^;=]+)/", $str, $matches);
$result = array_combine($matches[1], $matches[2]);

回答2:

Use parse_str for this: http://www.php.net/manual/en/function.parse-str.php

回答3:

You could explode by semicolon, then explode by =, and then use array_combine().

The solution is really not all that pretty, since it's quite verbose. I typed it out just in case, but you're probably better off with another method.

$s = "var=test;path=test.html";

$b = array_map(function($x){return explode("=", $x); }, explode(";", $s));
$c1 = array_map(function($x){return $x[0]; }, $b);
$c2 = array_map(function($x){return $x[1]; }, $b);

$result = array_combine($c1, $c2);

回答4:

How about str_replace?

$text = "var=test;path=test.html";
$text = str_replace(';',"\n\t", $text);
$text = str_replace('='," => ", $text);
echo <<<END
Array
{
\t$text
}
END;

You'll need to do some extra work to get the proper formatting, though

回答5:

I just figured out how you can do that by using the parse_str php built-in function.

From the php.ini documentation:

; List of separator(s) used by PHP to parse input URLs into variables.
; PHP's default setting is "&".
; NOTE: Every character in this directive is considered as separator!
; http://php.net/arg-separator.input
; Example:
;arg_separator.input = ";&"

So, if you do this:

ini_set('arg_separator.input', ';&');

The parse_str should explode query arguments both on ; and &. This shouldn't affect in any way the filling of $_GET and $_POST since they are loaded before your code execution. If you want to be sure you don't affect the behavior of any other function calling parse_str, you could use a function like this:

function my_parse_str($str, &$arr) {
    $orig = ini_get('arg_separator.input');
    ini_set('arg_separator.input', ';');
    parse_str($str, $arr);
    ini_set('arg_separator.input', $orig);
}

Two advantages over exploding on & and then on =:

Maximum execution speed since the parse_str() function is built-in
parse_str() also considers recursive splitting: a=1&a=2 -> array('a'=>array('1', '2')); or 'a[one]=1&a[two]=2' -> array('a'=>array('one'=>'1', 'two'=>'2')).

Update - performance benchmarking

I just run a test to compare the plain-php splitting vs parse_str(), on an array of 10000 query strings each made of 500 arguments. The my_parse_str() above took ~0.952 seconds, while the pure-php one (parseQueryString()) took ~4.25 seconds.

It would require a larger set of data to test exactly how much it is faster, but it's pretty clear which one wins :) (if you want the test data + scripts, I'll upload them somewhere, since the data file is 125MB).

来源：https://stackoverflow.com/questions/7381500/php-simple-string-to-array

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php

arrays