但是，如果您知道一个更好的解决方案来摆脱所有那些“未定义变量”警告，那么您可以度过我的一天。
有。修复未使用超全局变量的问题。现在，自然地，我并不是说您应该自己手动更改每个翻转变量调用，但我想这可能是您可以自动化的事情。看看你能不能跟随我的脑电波。
首先，您必须获得所有“未定义变量”通知的列表。这就像注册错误处理程序、检查 E_NOTICE 调用并检查它是否是未定义的变量调用一样简单。我冒昧地写了一小段代码来做到这一点。
<?php
/**
* GlobalsLog is a class which can be used to set an error handler which will
* check for undefined variables and checks whether they exist in superglobals.
*
* @author Berry Langerak
*/
class GlobalsLog {
/**
* Contains an array of all undefined variables which *are* present in one of the superglobals.
*
* @var array
*/
protected $globals;
/**
* This contains the order in which to test for presence in the superglobals.
*
* @var array
*/
protected $order = array( 'SERVER', 'COOKIE', 'POST', 'GET', 'ENV' );
/**
* This is where the undefined variables should be stored in, so we can replace them later.
*
* @var string
*/
protected $logfile;
/**
* Construct the logger. All undefined variables which are present in one of the superglobals will be stored in $logfile.
*
* @param string $logfile
*/
public function __construct( $logfile ) {
$this->logfile = $logfile;
set_error_handler( array( $this, 'errorHandler' ), E_NOTICE );
}
/**
* The error handler.
*
* @param int $errno
* @param string $errstr
* @param string $errfile
* @param int $errline
* @return boolean
*/
public function errorHandler( $errno, $errstr, $errfile, $errline ) {
$matches = array( );
if( preg_match( '~^Undefined variable: (.+)$~', $errstr, $matches ) !== 0 ) {
foreach( $this->order as $superglobal ) {
if( $this->hasSuperglobal( $superglobal, $matches[1] ) ) {
$this->globals[$errfile][] = array( $matches[1], $superglobal, $errline );
return true;
}
}
}
}
/**
* Called upon destruction of the object, and writes the undefined variables to the logfile.
*/
public function __destruct( ) {
$globals = array_merge( $this->globals, $this->existing( ) );
file_put_contents(
$this->logfile,
sprintf( "<?php\nreturn %s;\n", var_export( $globals, true ) )
);
}
/**
* Gets the undefined variables that were previously discovered, if any.
*
* @return array
*/
protected function existing( ) {
if( file_exists( $this->logfile ) ) {
$globals = require $this->logfile;
return $globals;
}
return array( );
}
/**
* Checks to see if the variable $index exists in the superglobal $superglobal.
*
* @param string $superglobal
* @param string $index
* @return bool
*/
protected function hasSuperglobal( $superglobal, $index ) {
return array_key_exists( $index, $this->getSuperglobal( $superglobal ) );
}
/**
* Returns the value of the superglobal. This has to be done on each undefined variable, because
* the session superglobal maybe created *after* GlobalsLogger has been created.
*
* @param string $superglobal
* @return array
*/
protected function getSuperglobal( $superglobal ) {
$globals = array(
'SERVER' => $_SERVER,
'COOKIE' => $_COOKIE,
'POST' => $_POST,
'GET' => $_GET,
'ENV' => $_ENV
);
return isset( $globals[$superglobal] ) ? $globals[$superglobal] : array( );
}
}
/**
* Lastly, instantiate the object, and store all undefined variables that exist
* in one of the superglobals in a file called "undefined.php", in the same
* directory as this file.
*/
$globalslog = new GlobalsLog( __DIR__ . '/undefined.php' );
如果您要在请求的每个页面中包含此文件（可选地使用php_prepend_file），在单击整个应用程序后，您最终会在“undefined.php”中得到所有未定义的变量。
这是相当有趣的信息，因为您现在知道哪个未定义变量位于哪个文件中、在哪一行以及它实际存在于哪个超全局中。在确定超全局时，我记住了 Environment、Get、Post、Cookie 和 Server 的顺序，以决定哪个优先。
对于我们巧妙的小技巧的下一部分，我们必须遍历所有undefined variable发现通知的文件，并尝试将未定义的变量替换为其超全局变量。这实际上也很简单，我再次创建了一个脚本来执行此操作：
#!/usr/bin/php
<?php
/**
* A simple script to replace non globals with their globals counterpart.
*/
$script = array_shift( $argv );
$logfile = array_shift( $argv );
$backup = array_shift( $argv ) === '--backup';
if( $logfile === false || !is_file( $logfile ) || !is_readable( $logfile ) ) {
print "Usage: php $script <logfile> [--backup].\n";
exit;
}
$globals = require $logfile;
if( !is_array( $globals ) || count( $globals ) === 0 ) {
print "No superglobals missing found, nothing to do here.\n";
exit;
}
$replaced = 0;
/**
* So we have the files where superglobals are missing, but shouldn't be.
* Loop through the files.
*/
foreach( $globals as $filename => $variables ) {
if( !is_file( $filename ) || !is_writable( $filename ) ) {
print "Can't write to file $filename.\n";
exit;
}
foreach( $variables as $variable ) {
$lines[$variable[2]] = $variable;
}
/**
* We can write to the file. Read it in, line by line,
* and see if there's anything to do on that line.
*/
$fp = fopen( $filename, 'rw+' );
$i = 0;
$buffer = '';
while( $line = fgets( $fp, 1000 ) ) {
++$i;
if( array_key_exists( $i, $lines ) ) {
$search = sprintf( '$%s', $lines[$i][0] );
$replace = sprintf( "\$_%s['%s']", $lines[$i][1], $lines[$i][0] );
$line = str_replace( $search, $replace, $line );
$replaced ++;
}
$buffer .= $line;
}
if( $backup ) {
$backupfile = $filename . '.bck';
file_put_contents( $backupfile, file_get_contents( $filename ) );
}
file_put_contents( $filename, $buffer );
}
echo "Executed $replaced replacements.\n";
unlink( $logfile );
现在，只需调用此脚本即可。我已经对此进行了测试，这是我测试过的文件：
<?php
require 'logger.php';
$_GET['foo'] = 'This is a value';
$_POST['foo'] = 'This is a value';
$_GET['bar'] = 'test';
function foo( ) {
echo $foo;
}
foo( );
echo $bar;
有两个未定义的变量（$foo和$bar），它们都存在于一个（或多个）超全局变量中。在我的浏览器中访问该页面后，我的日志文件中有两个条目undefined.php；即 foo 和 bar。然后，我运行了php globalsfix.php undefined.php --backup给我以下输出的命令：
berry@berry-pc:/www/public/globalfix% php globalsfix.php undefined.php --backup
Executed 2 replacements.
好奇结果如何？好吧，我也是。这里是：
<?php
require 'logger.php';
$_GET['foo'] = 'This is a value';
$_POST['foo'] = 'This is a value';
$_GET['bar'] = 'test';
function foo( ) {
echo $_POST['foo'];
}
foo( );
echo $_GET['bar'];
万岁！没有更多未定义的变量，这些是从正确的超全局变量中读取的。大胖免责声明：先创建备份。此外，这不会立即解决您的所有问题。如果你有一个if( $foo )语句，未定义的变量将确保相应的块永远不会被执行，这意味着很可能不是所有未定义的变量都会一次被捕获（但它会在第二次或第三次使用此脚本时解决该问题） . 尽管如此; 这是开始“清理”代码库的好地方。
另外，恭喜您阅读了我的全部答案。:)