PHP supports eight primitive types.
Four scalar types:
Two compound types:
And finally two special types:
This manual also introduces some
pseudo-types
for readability reasons:
You may also find some references to the type "double". Consider
double the same as float, the two names exist only for historic
reasons.
The type of a variable is usually not set by the programmer;
rather, it is decided at runtime by PHP depending on the context in
which that variable is used.
Note:
If you want to check out the type and value of a certain expression, use
var_dump().
Note:
If you simply want a human-readable representation of the type for
debugging, use gettype(). To check for a certain type,
do not use gettype(), but use the
is_type functions. Some
examples:
If you would like to force a variable to be converted to a certain
type, you may either cast the variable or
use the settype() function on it.
Note that a variable may be evaluated with different values in certain
situations, depending on what type it is at the time. For more
information, see the section on Type Juggling. Also, you
may be interested in viewing
the type comparison tables,
as they show examples of various type related comparisons.
