来自MSDN中的原文: The operand to sizeof can be one of the following:
A type name. To use sizeof with a type name, the name must be enclosed in parentheses.
An expression. When used with an expression, sizeof can be specified with or without the parentheses. The expression is not evaluated.
When the sizeof operator is applied to an object of type char, it yields 1. When the sizeof operator is applied to an array, it yields the total number of bytes in that array, not the size of the pointer represented by the array identifier. To obtain the size of the pointer represented by the array identifier, pass it as a parameter to a function that uses sizeof. For example:
