如何在php中使用「for」循環創建動態增量變量？

Question

如何在php中使用「for」循環創建動態增量變量？ 喜歡聰明：$ track_1，$ track_2，$ track_3，$ track_4 .....等等....

Answer 1

使用parse_str()或${'track_' . $i} = 'val';。

Answer 2

<? 
for($i = 0; $i < 10; $i++) { 
    $name = "track_$i"; 
    $$name = 'hello'; 
} 

print("==" . $track_3); 

Answer 3

<?php 

for ($i = 1; $i <= 3; $i++) { 
    ${"track_{$i}"} = 'this is track ' . $i; // use double quotes between braces 
} 

echo $track_1; 
echo '<br />'; 
echo $track_3; 

?> 

這也適用於嵌套瓦爾：

<?php 

class Tracks { 
    public function __construct() { 
     $this->track_1 = 'this is friend 1'; 
     $this->track_2 = 'this is friend 2'; 
     $this->track_3 = 'this is friend 3'; 
    } 
} 

$tracks = new Tracks; 

for ($i = 1; $i <= 3; $i++) { 
    echo $tracks->{"track_{$i}"}; 
    echo '<br />'; 
} 

?>