• In a programmer, error is a mistake that may be caused by writing incorrect code or incorrect syntax.
• An error message is displayed on your browser containing the filename along with a message describing the error, location and the line number in which error has occurred.
• In PHP there are various types of errors that contains basically four main types of errors, they are
  • Syntax Error or Parse Error
  • Fatal Error
  • Warning Error
  • Notice Error

Syntax Error or Parse Error

• A syntax error is a mistake in the syntax of source code, which can be done by programmers due to their lack of knowledge or concern.
• At compile time compiler is used to catch the syntax error.
• Due to common reasons these errors can occur like missing semicolon, unclosed quotes, or unclosed brackets, extra or missing parentheses and many more.
• While compiling the program syntax error can be caught by the compiler and gives a syntax error or parse error message.

Sample Code

<?php  
    /*------------------syntax error-------------------*/  
    echo "Venkat: Hie! I'm Venkat. </br>";  
    echo "Lokesh: I'm Lokesh. How are you?"  
    echo "Venkat: I'm good! and you?";  
    echo "Lokesh: I'm also good";  
?>  

Output

Fatal Error

• Fatal error is another type of error, which is occurred due to the use of undefined function.
• The PHP compiler understands the PHP code and also recognizes the undefined function.
• PHP compiler generates a fatal error, when a function is called without providing its definition.

Sample Code

<?php  
    /*------------------fatal error-------------------*/  
    function add($f1, $f2) {  
        $sum = $f1 + $f2;  
        echo "Addition:" . $sum;  
    }  
      
    $f1 = 23;  
    $f2 = 56;  
      
    //call the function that is not defined  
    //Generate fatal error  
    catch_fatal_error();  
    //echo "Fatal Error";     
?>  

Output

Warning Error

• When the programmer tries to include a missing file there warning error is generated.
• The PHP function calls that missing file which does not exist and warning error does not stop/prevent the execution of the program.

Sample Code

<?php  
    /*-------------------warning error------------------*/  
    $cmpny = 'Wikitechy';  
    echo "Warning Error: ";  
      
    //include a file in the code  
    include ('jtp.php');      
?>

Output

Notice Error

• Notice error is also same as warning error, when program contains something wrong, the notice error occurs.
• Including a notice error, it allows/continue the execution of the program.
• Notice error does not prevent the execution of the code and generally it occurs when we try to use or access a variable which is undefined.

Sample Code

<?php  
    /*------------------notice error-------------------*/  
    $telecom = "Airtel";  
    echo $telecom;  
    echo $automobile;  
?>  

Output