PHP Tutorial - PHP Data Type Cast

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type casting can cause a variable's value to be treated as a specific type.

Syntax

Placing the name of the desired data type in parentheses before the variable's name.

variableName1 = (newType)variableName2;

or

variableName1 = (newType)variableName1;

The second form cast to itself.

Example - PHP data type casting

In the following example, a variable's value is cast to various different types at the time that the value is displayed:

<?PHP
       $test_var = 8.23; 
       echo $test_var;             // Displays "8.23" 
       echo (string)$test_var;     // Displays "8.23" 
       echo (int) $test_var;       // Displays "8" 
       echo (float) $test_var;     // Displays "8.23" 
       echo (boolean) $test_var;   // Displays "1"   
?>

The code above generates the following result.

$test_var's type isn't changed at any point. It remains a floating - point variable, containing the value 8.23.

Casting list

Here's the full list of casts that you can use in PHP:

Function	Description
(int) value or (integer) value	Returns value cast to an integer
(float) value	Returns value cast to a float
(string) value	Returns value cast to a string
(bool) value or (boolean) value	Returns value cast to a Boolean
(array) value	Returns value cast to an array
(object) value	Returns value cast to an object

PHP Automatic Type Conversion

PHP automatically converts one type of variable to another whenever possible.

Example - Convert integer to string

<?PHP
$mystring = "12"; 
$myinteger = 20; 
print $mystring + $myinteger; 
?>

The code above generates the following result.

That script will output 32.

Example - Convert boolean to string and integer

Converting from a boolean to a string will produce a 1 if the boolean is set to true, or an empty string if false.

Consider this script:

<?PHP
$bool = true; 
print "Bool is set to $bool\n"; 
$bool = false; 
print "Bool is set to $bool\n"; 
?>

The code above generates the following result.

We can solve this problem by typecasting.

<?PHP
$bool = true; 
print "Bool is set to $bool\n"; 
$bool = false; 
print "Bool is set to "; 
print (int)$bool; 
?>

The code above generates the following result.

This time the script outputs 1 and 0 as we wanted.

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