Home > Backend Development > PHP Tutorial > Detailed introduction to exception handling code examples in PHP7

Detailed introduction to exception handling code examples in PHP7

黄舟
Release: 2023-03-06 14:10:02
Original
1386 people have browsed it

Preface

Among the changes in PHP7, those that have a greater impact include Exception handling.

Overview

More exceptions are handled directly through PHP. Different from the previous PHP5, more exceptions are thrown through Error exceptions.

As a normal extension, Error exceptions will continue to pop up until the corresponding catch block is matched. If no match is made, the set set_exception_handler() will be triggered to perform processing. If there is no default exception handler, the exception will be converted to a fatal error and will be treated like a traditional The error is handled.

Since Error does not inherit exceptions in the error hierarchy, code like this catch (Exception $e) { ... } will not catch the corresponding exception in PHP5. We can use the code catch (Error $e) { ... } or set_exception_handler() to handle Error.

Wrong hierarchy

  • Throwable

    • ##….

    • ArithmeticError Arithmetic Error


    • AssertionError Statement Error

    • ParseError Parse Error

    • TypeError Type error

    • pisionByZeroError Divisor by 0 error

    • Error Error


    • Exception Exception


PHP RFC

Throwable Interface

function add(int $left, int $right) {
    return $left + $right;
}try {    echo add('left', 'right');
} catch (Exception $e) {    // Handle exception} catch (Error $e) { // Clearly a different type of object
    // Log error and end gracefully
    var_dump($e);
}
Copy after login

Here, there is no server 500 error. The reason is that the Error in PHP7 intercepts it and does not bubble up in the server.

object(TypeError)#1 (7) {
  ["message":protected]=>  
  string(139) "Argument 1 passed to add() must be of the type integer, string given, called in /Applications/mamp/apache2/htdocs/curl/error.php on line 14"
  ["string":"Error":private]=>  string(0) ""
  ["code":protected]=>  int(0)
  ["file":protected]=>  string(48) "/Applications/mamp/apache2/htdocs/curl/error.php"
  ["line":protected]=>  int(9)
  ["trace":"Error":private]=>
  array(1) {
    [0]=>
    array(4) {
      ["file"]=>      string(48) "/Applications/mamp/apache2/htdocs/curl/error.php"
      ["line"]=>      int(14)
      ["function"]=>      string(3) "add"
      ["args"]=>
      array(2) {
        [0]=>        string(4) "left"
        [1]=>        string(5) "right"
      }
    }
  }
  ["previous":"Error":private]=>
  NULL
}
Copy after login

So we can record them through logs.

Exceptions in the engine (for PHP 7)

function call_method($obj) {
    $obj->method();
}try {
    call_method(null);
     // oops!
     } 
     catch (EngineException $e) {    
    echo "Exception: {$e->getMessage()}\n";
}//其实上面的例子我在运行过程中,并没有被EngineException捕获异常,经过测试,也是通过Error进行的错误的拦截
Copy after login

If the exception is not caught, PHP will continue to throw the same fatal error as it currently does.

Reclassify E_STRICT notices


The above is the detailed content of Detailed introduction to exception handling code examples in PHP7. For more information, please follow other related articles on the PHP Chinese website!

Related labels:
source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template