php 基礎資料型別 (Elementary Data Type)

PHP has a total of eight types: integers, doubles, Booleans, strings, arrays, objects, NULL, and

resources.

✦Integers are whole numbers, without a decimal point, like 495. ✦ Doubles are floating-point numbers, like 3.14159 or 49.0. ✦ Booleans have only two possible values: TRUE and FALSE. ✦ NULL is a special type that only has one value: NULL. ✦ Strings are sequences of characters, like ‘PHP 4.0 supports string operations.’ ✦ Arrays are named and indexed collections of other values. ✦ Objects are instances of programmer-defined classes, which can package up both other kinds of values and functions that are specific to the class. ✦ Resources are special variables that hold references to resources external to PHP (such as database connections).

 

Of these, the first five are simple types, and the next two (arrays and objects) are compound—
the compound types can package up other arbitrary values of arbitrary type, whereas the
simple types cannot.