Union(联合) 问题
#include <iostream>union Holder
{
char holdchar;
short int holdint;
long int holdlong;
float holdfloat;
};
// Function prototype.
void DisplayHolder(Holder, char*);
int main()
{
Holder hld;
// Assign to first member.
hld.holdchar = 'X';
DisplayHolder(hld, "char");
hld.holdint = 12345;
DisplayHolder(hld, "int");
hld.holdlong = 7654321;
DisplayHolder(hld, "long");
hld.holdfloat = 1.23;
DisplayHolder(hld, "float");
return 0;
}
void DisplayHolder(Holder hld, char* tag)
{
std::cout << "---Initialized " << tag << " ---"
<< std::endl;
std::cout << "holdchar " << hld.holdchar << std::endl;
std::cout << "holdint " << hld.holdint << std::endl;
std::cout << "holdlong " << hld.holdlong << std::endl;
std::cout << "holdfloat " << hld.holdfloat << std::endl;
}
疑问:
1) tag 是什么 ?
2)不明白 --initialized char-- 的 输出 怎样來的, thank you very much !!!
