提高預浸料/ PCRE /正則表達式來找到PHP變量

Question

字符串解析：

$str = " 
public $xxxx123; 
private $_priv ; 
     $xxx  = 'test'; 
private $arr_123 = array(); 
"; // |  | 
    //  ^^^^^^^---- get the variable name 

我有什麼至今：

$str = preg_match_all('/\$\S+(;|[[:space:]])/', $str, $matches); 
    foreach ($matches[0] as $match) { 
     $match = str_replace('$', '', $match); 
     $match = str_replace(';', '', $match); 
    } 

它的工作原理，但我想，如果我能知道改進preg，例如干掉兩個str_replace的，也許包括\t在(;|[[:space:]])

Answer 1

使用正回顧後，你可以得到只，你需要什麼，相信你一定會只匹配有效變量名，我用這個：

preg_match_all('/(?<=\$)[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*/',$str,$matches); 
var_dump($matches); 

其正確地顯示：

 
array (
    0 => 
    array (
    0 => 'xxxx123', 
    1 => '_priv', 
    2 => 'xxx', 
    3 => 'arr_123' 
) 
) 

這就是你所需要的，沒有內存在包含所有變量及其前導和/或尾隨字符的數組上。

表達：

• (?<=\$)是一種積極的回顧後
• [a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*：是PHP的網站上介紹自己的正則表達式on their document pages

Answer 2

只需使用反向引用

preg_match_all('/\$(\S+?)[;\s=]/', $str, $matches); 
foreach ($matches[1] as $match) { 

    // $match is now only the name of the variable without $ and ; 
} 

Answer 3

我改變了正則表達式一點點，一起來看看：

$str = ' 
public $xxxx123; 
private $_priv ; 
     $xxx  = "test"; 
private $arr_123 = array(); 
'; 

$matches = array(); 

//$str = preg_match_all('/\$(\S+)[; ]/', $str, $matches); 
$str = preg_match_all('/\$(\S+?)(?:[=;]|\s+)/', $str, $matches); //credits for mr. @booobs for this regex 

print_r($matches); 

輸出：

Array 
(
    [0] => Array 
     (
      [0] => $xxxx123; 
      [1] => $_priv 
      [2] => $xxx 
      [3] => $arr_123 
     ) 

    [1] => Array 
     (
      [0] => xxxx123 
      [1] => _priv 
      [2] => xxx 
      [3] => arr_123 
     ) 

) 

現在您可以使用$matches[1]在foreach循環中。

::更新::

使用正則表達式「後/ \ $（[A-ZA-Z_ \ x7f- \ XFF] [A-ZA-Z0-9_ \ x7f- \ XFF] *）/ 「輸出看起來正確。

字符串：

$str = ' 
public $xxxx123; $input1;$input3 
private $_priv ; 
     $xxx  = "test"; 
private $arr_123 = array(); 

「;

和輸出：

Array 
(
    [0] => Array 
     (
      [0] => $xxxx123 
      [1] => $input1 
      [2] => $input3 
      [3] => $_priv 
      [4] => $xxx 
      [5] => $arr_123 
     ) 

    [1] => Array 
     (
      [0] => xxxx123 
      [1] => input1 
      [2] => input3 
      [3] => _priv 
      [4] => xxx 
      [5] => arr_123 
     ) 

)