错误处理 函数
在线手册：中文 英文
PHP手册

restore_error_handler

(PHP 4 >= 4.0.1, PHP 5)

restore_error_handler — Restores the previous error handler function

说明

bool restore_error_handler ( void )

Used after changing the error handler function using set_error_handler(), to revert to the previous error handler (which could be the built-in or a user defined function).

返回值

This function always returns TRUE.

范例

Example #1 restore_error_handler() example

Decide if unserialize() caused an error, then restore the original error handler.

<?php
function unserialize_handler($errno, $errstr)
{
    echo "Invalid serialized value.\n";
}

$serialized = 'foo';
set_error_handler('unserialize_handler');
$original = unserialize($serialized);
restore_error_handler();
?>

以上例程会输出：

Invalid serialized value.

注释

Note:

Calling restore_error_handler() from the error_handler function is ignored.

参见

错误处理 函数
在线手册：中文 英文
PHP手册
PHP手册 - N: Restores the previous error handler function

用户评论:

webmaster at travian dot lu (01-Jul-2011 05:27)

If you don't know how often you'd need to call restore_error_handler() to restore the built-in error handler, just do:

<?php

set_error_handler(function() {
  return false;
});

?>

Timo Frenay (31-Aug-2009 12:23)

While looking through some old code I found this trick I once used for restoring the built-in error handler:

<?php
    // Unwind the error handler stack until we're back at the built-in error handler.
    function unset_error_handler()
    {
        while (set_error_handler(create_function('$errno,$errstr', 'return false;'))) {
            // Unset the error handler we just set.
            restore_error_handler();
            // Unset the previous error handler.
            restore_error_handler();
        }
        // Restore the built-in error handler.
        restore_error_handler();
    }
?>

sebagr gmail com (22-May-2008 04:54)

I think what Isole wanted to say is that if you push the same error handler twice, then you'll need to call restore_error_handler() twice if you want to get rid of it:

<?php
function custom_error_handler(){
    echo 'My error handler';
    return false;
}

set_error_handler('custom_error_handler'); // Stack is: <default error handler> | custom_error_handler
set_error_handler('custom_error_handler'); // Stack is: <default error handler> | custom_error_handler | custom_error_handler

trigger_error('error', E_USER_WARNING); // Will print 'My error handler';

restore_error_handler(); // The stack is <default error handler> | custom_error_handler

trigger_error('error', E_USER_WARNING); // Will still print 'My error handler', since the stack is still dirty with our first custom_error_handler.

restore_error_handler(); // The stack is <default error handler>

trigger_error('error', E_USER_WARNING); // Now this will trigger the default error handler.

?>

edgarinvillegas at hotmail dot com (28-Mar-2008 04:21)

Isolde is kind of wrong. The error handlers are stacked with set_error_handler(), and popped with restore_error_handler(). Here i put an example:

<?php
    mysql_connect("inexistent"); //Generate an error. The actual error handler is set by default

    function foo1() {echo "<br>Error foo1<br>";}
    function foo2() {echo "<br>Error foo2<br>";}
    function foo3() {echo "<br>Error foo3<br>";}
   
    set_error_handler("foo1");    //current error handler: foo1
    set_error_handler("foo2");    //current error handler: foo2
    set_error_handler("foo3");    //current error handler: foo3
   
    mysql_connect("inexistent");   
    restore_error_handler();        //now, current error handler: foo2
    mysql_connect("inexistent");    
    restore_error_handler();        //now, current error handler: foo1
    mysql_connect("inexistent");
    restore_error_handler();        //now current error handler: default handler
    mysql_connect("inexistent");
    restore_error_handler();        //now current error handler: default handler (The stack can't pop more)
?>

lsole at maresme dot net (14-Mar-2004 07:57)

As the docs say, restore_error_handler() revert to the *previous error handler*... even if it is the same. A bug made me set twice my custom error handler and later when I was calling restore_error_handler() to restore the built-in handler nothing seemed to happen... this puzzled me for a while!