PHP through the trigger

This article mainly introduces PHP through the trigger_error to trigger a PHP error example, this article describes the error suppressor @ and through the Trigger_error trigger PHP error example, the need for friends can refer to the

Example of PHP error triggered by Trigger_error in PHP

"Error suppressor @"

In addition to the error_reporting and display_errors settings in PHP.ini, the error_reporting () function, the Ini_set () function, you can also use the error suppressor @ to mask the wrong output.

@ Plus before any expression that will produce an error.

"Trigger PHP error via Trigger_error"

The ability to trigger the error is not limited to the PHP parser, it can also trigger an error through the Trigger_error () function, similar to the exception thrown in the exception, throws an error that can assist in debugging the code.

Cases

The code is as follows:

　　

$num 1 = 1;

$num 2 = ' 2 ';

if (!) ( Is_numeric ($num 1) && is_numeric ($num 2))) {

Error of manually throwing notification level

Trigger_error (' Num1 and num2 must be legal values ', e_user_notice);

}else{

echo $num 1 + $num 2;

}

Echo '
The program continues to execute downward ';

Output:

The code is as follows:

3

Program continues down execution

and

The code is as follows:

　　

$num 1 = 1;

$num 2 = ' 2a ';

if (!) ( Is_numeric ($num 1) && is_numeric ($num 2))) {

Error of manually throwing notification level

Trigger_error (' Num1 and num2 must be legal values ', e_user_notice);

}else{

echo $num 1 + $num 2;

}

Echo '
The program continues to execute downward ';

Output:

The code is as follows:

( ! ) NOTICE:NUM1 and num2 must be valid values in d:practisephperrorerror1.php on line 6

Program continues down execution

"Other" when serious errors such as the database is not connected, you can manually throw the error-replace the PHP built-in e_warning warning with E_user_error.