结构体和联合体配合使用

typedef union
{
    struct
    {
        uint8  Key_PushDownFlag       :1;
        uint8  Key_CheckFlag          :1;
        uint8  Key_ContinueFlag       :1;
        uint8  Key_ValidFlag          :1;
        uint8  RevFlag                :4;
    }bit;
    uint8 KeyFlagBuf;
}KEYFlag_Union;

KevFlag 和结构体bit 共享一个字节存储空间