# 关键字static

用static声明的静态成员函数不与特定的对象相关联，不能通过对象来调用，也不能使用this。用static修饰后的成员函数就会被编译放入静态存储区，所以不会与栈区或者堆区的对象有联系。但是调用的时候需要带上类命名空间来调用。静态成员函数只能使用静态数据成员。

```c++
static int HowMany(){
    return num_strings;
}
//调用
int count = String::HowMany();
```


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