PHP Exception Handling

The first thing to happen is an exception!

The so-called occurrence, refers to throwing an exception!

Then deal with the exception!

The so-called treatment, that is, once an anomaly occurs, to get and deal with this anomaly, there are usually two stages: monitoring and capturing!

Process:

1. Throw Exception Throw

2. Listen for exception try

3. Catching exception catch

Note: the exception here, in fact, is an exception object, this object must be the system pre-defined exception class (class named Exception) or its subclasses instantiated!

Example:

<?PHPEcho"<meta charset=utf-8>";classgoods{ Public functionGetPrice () {$price=$_get[' P ']; //exception Handling If the price is less than 0        if($price<0) {            //instantiate an exception object            $e=New Exception($message= ' Price cannot be negative! ‘); Throw $e;//Throw Exception}Else{            Echo $price; }    }}//Exception HandlingTry{    //listen to the code    $good=NewGoods; $good-GetPrice ();}Catch(Exception $e){    //Catching exceptions    Echo"Error message is:".$e->getmessage (). " <br/> "; Echo"Error code is:".$e->getcode (). " <br/> "; Echo"Error file is:".$e->getfile (). " <br/> "; Echo"The error line number is:".$e->getline (). " <br/> ";}

Results: The input parameter p=22 (greater than 0) shows normal, not throwing an exception!

If the parameter p=-22 (less than 0) is passed, the result is as follows

The next article introduces the exception handling in PDO

PHP Exception Handling