对一个无符号字符变量左移8位表示啥？

[幽雾]

请大牛解答，对一个无符号字符变量左移8位表示啥啊？然后再与另一个无符号字符变量逻辑或。迷惑不解

unsigned char uc1;
uc1 << 8;//表示啥

unsigned char uc2;
(uc1 << 8) | uc2;//再与uc2逻辑或，表示啥

[赵4老师]

仅供参考

//The _getch function reads a single character from the console without echoing.
//Function can not be used to read CTRL+Break.
//When reading a function key or an arrow key,
//_getch must be called twice; the first call returns 0 or 0xE0,
//and the second call returns the actual key code.
#include <conio.h>
#include <windows.h>
void main() {
    unsigned short k;

    while (1) {
        Sleep(100);
        k=getch();
        if (27==k) break;//按Esc键退出
        if (0==k||0xe0==k) k|=getch()<<8;//非字符键
        cprintf("%04x pressed.\r\n",k);
    }
}

[W170532934]

uc1<<8在寄存器中会显示低8位为0，原来的uc1的值移到了第7--16位。
与uc2或后，寄存器应该是7--16位是uc1，低8位是uc2.然后就看你这个寄存器内的值赋值给谁了。

[qq120848369]

就是Uc2吧