How to catch error of require() or include() in PH

问题:

I'm writing a script in PHP5 that requires the code of certain files. When A file is not available for inclusion, first a warning and then a fatal error are thrown. I'd like to print an own error message, when it was not possible to include the code. Is it possible to execute one last command, if requeire did not work? the following did not work:

require('fileERROR.php5') or die("Unable to load configuration file.");

Supressing all error messages using error_reporting(0) only gives a white screen, not using error_reporting gives the PHP-Errors, which I don't want to show.

回答1:

You can accomplish this by using set_error_handler in conjunction with ErrorException.

The example from the ErrorException page is:

<?php
function exception_error_handler($errno, $errstr, $errfile, $errline ) {
    throw new ErrorException($errstr, $errno, 0, $errfile, $errline);
}
set_error_handler("exception_error_handler");

/* Trigger exception */
strpos();
?>

Once you have errors being handled as exceptions you can do something like:

<?php
try {
    include 'fileERROR.php5';
} catch (ErrorException $ex) {
    echo "Unable to load configuration file.";
    // you can exit or die here if you prefer - also you can log your error,
    // or any other steps you wish to take
}
?>

回答2:

I just use 'file_exists()':

if (file_exists("must_have.php")) {
    require "must_have.php";
}
else {
    echo "Please try back in five minutes...\n";
}

回答3:

A better approach would be to use realpath on the path first. realpath will return false if the file does not exist.

$filename = realpath(getcwd() . "/fileERROR.php5");
$filename && return require($filename);
trigger_error("Could not find file {$filename}", E_USER_ERROR);

You could even create your own require function in your app's namespace that wraps PHP's require function

namespace app;

function require_safe($filename) {
  $path = realpath(getcwd() . $filename);
  $path && return require($path);
  trigger_error("Could not find file {$path}", E_USER_ERROR);
}

Now you can use it anywhere in your files

namespace app;

require_safe("fileERROR.php5");

回答4:

I would suggest you took a look at the most recent comment in the documentation for the set_error_handler() function.

It suggests the following as a method (and with an example) of catching fatal errors:

<?php
function shutdown()
{
    $a=error_get_last();
    if($a==null)  
        echo "No errors";
    else
         print_r($a);

}
register_shutdown_function('shutdown');
ini_set('max_execution_time',1 );
sleep(3);
?> 

I haven't tried the suggestion, but this could propably be used in other fatal error scenarios.

回答5:

You need to use include(). Require(), when used on non-existent file, produces a fatal error and exits the script, so your die() won't happen. Include() only throws warning and then the script continues.

回答6:

A simple way I am using is that

<?php
    ...
    if(!include 'config.php'){
        die("File not found handler. >_<");
    }
   ...
?>