class T{
public:
T(int):name("fangrk"){age=25;}//1 OK
T(float):name("fangrk"),age(25){}//2 OK
T(){string="fangrk";age=25;}//3 ERROR
private:
int age;
string name;
}
constructor定义式的第二种初始化语法,是所谓的member initialization list
为了将name的初值传给string constructor,必须以member initialization list完成(《Essential C++》p106)