Question

我正在使用preg_mat替换模板中的if语句。我一直试图从preg_match_all获取匹配并从匹配中获得结果并使用preg_replace，但我得到偏移错误。

非常感谢对语法的任何帮助。同样好奇是否有更好的方法来解决这个问题。

代码示例：

public function output() {

$output = file_get_contents($this->file);

foreach ($this->values as $key => $value) {
    $tagToReplace = "[@$key]";
    $output = str_replace($tagToReplace, $value, $output);

    $dynamic = preg_quote($key);
    $pattern = '%\[if @'.$dynamic.'\](.*?)\[/if\]%'; // produces: %\[if @username\](.*?)\[/if\]%

    if ($value == '') {
    $output = preg_replace($pattern, "", $output);  
    } else {
    preg_match_all($pattern, $output, $if_match);
    $output = preg_replace("%\[if @".$dynamic."\]%", "", $if_match[0][0]);
    $output = preg_replace("%\[/if]%", "", $if_match[0][0]);        
    }

模板除外：

    [if @username] <p>A statement goes here and this is [@username]</p> [/if]
    [if @sample] <p>Another statement goes here</p> [/if]

控制器摘录：

$layout->set("username", "My Name");
$layout->set("sample", "");

Answer 1

使用回调然后在$ matches上运行preg_replace解决了问题：

public function output() {

$output = file_get_contents($this->file);

foreach ($this->values as $key => $value) {
    $tagToReplace = "[@$key]";
    $output = str_replace($tagToReplace, $value, $output);

    $dynamic = preg_quote($key);
    $pattern = '%\[if @'.$dynamic.'\](.*?)\[/if\]%'; // produces: %\[if @username\](.*?)\[/if\]%

    if ($value == '') {
    $output = preg_replace($pattern, "", $output);  
    } else {
    $callback = new MyCallback($key, $value);
    $output = preg_replace_callback($pattern, array($callback, 'callback'), $output);
    }

}

return $output;
}


}

class MyCallback {
private $key;
private $value;

function __construct($key, $value) {
    $this->key = $key;
    $this->value = $value;
}

public function callback($matches) {

    $matches[1] = preg_replace("%\[if @".$this->key."\]%", "", $matches[1]);
    $matches[1] = preg_replace("%\[/if]%", "", $matches[1]);

    return $matches[1];
}
}

使用preg_match_all结果与preg_replace有关的问题

1 个答案: