Try to execute some code and catch the error which the code thrown. It is also called error handling.
try-catch Block
try{
//some code and throw exception
}catch(\Exception $e){
//do something with the errors
}
The Example of try-catch Block
<?php
if(!empty($_POST)){
$username = $_POST['username'];// sterilize in production mode
$password = $_POST['password'];// sterilize in production mode
/*
// throw an exception
if(empty($username) || empty($password)){
throw new \Exception('Invalid Username or Password.');
}
*/
}
?>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- css -->
<link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css"
type="text/css" />
<!-- javascript -->
<script src="https://cdn.jsdelivr.net/gh/jquery/[email protected]/dist/jquery.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container">
<form method="post" action="index.php">
<h1>
PHP try catch example
</h1>
<div class="form-group">
<label for="username">Username</label>
<input type="text" class="form-control" id="username" name="username" />
</div>
<div class="form-group">
<label for="username">Password</label>
<input type="password" class="form-control" id="password" name="password" />
</div>
<div class="form-group">
<div class="alert alert-danger">
<?php
try{
if(empty($username) || empty($password)){
throw new \Exception('Invalid Username or Password.');
}
}catch(\Exception $e){
echo $e->getMessage();
}
?>
</div>
</div>
<button type="submit" class="btn btn-primary">Submit</button>
</form>
</div>
</body>
</html>

You can download all the code here: bruce-lab/php-try-catch