根据位数取值，C语言位操运算

#include

 

unsigned char read_bit_fun(unsigned char name,int begin,int num);

 

int main()
{

   unsigned char c;

   c=read_bit_fun(0xff,0,8);
   printf("%d\n",c);

return 0;

}

 

/*取位值函数定义*/
 unsigned char read_bit_fun(unsigned char name,int begin,int num)
 {
                        //0    1     2   3    4     5   6     7   8
 unsigned char value[]={0x01,0x01,0x03,0x07,0x0f,0x1f,0x3f,0x7f,0xff};
 unsigned char bit;
 bit=(name>>begin)&(value[num]);
 //printf("bit=%x\n",(name>>begin)&(value[num]));
 return bit;
 }