PHP Variable functions

The PHP boolval() function converts a value to boolean.

The PHP empty() construct checks whether a variable is empty.

The PHP floatval() function converts a value to a floating-point number.

The PHP gettype() function returns the type of a variable as a string.

The PHP intval() function converts a value to an integer.

The PHP is_array() function checks whether a variable is an array.

The PHP is_bool() function checks whether a variable is of type boolean.

The PHP is_float() function checks whether a variable is of type float.

The PHP is_int() function checks whether a variable is of type integer.

The PHP is_null() function checks whether a variable is null.

The PHP is_numeric() function checks whether a variable is a number or numeric string.

The PHP is_object() function checks whether a variable is an object.

The PHP is_string() function checks whether a variable is of type string.

The PHP isset() construct checks whether a variable is set and not null.

The PHP settype() function sets the type of a variable.