十进制转换成十六进制、16进制转2进制

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <locale.h>
int main() {
    int i,v;
    char bs[33];
    char b[33];
    char hs[9];
    char h[9];
    char s[4];
    char *e;

// 十进制整数转二进制串；
    i=1024;
    ltoa(i,b,2);
    sprintf(bs,"%032s",b);
    printf("i=%d,bs=%s
",i,bs);
// 十进制整数转十六进制串；
    i=1024;
    ltoa(i,h,16);
    sprintf(hs,"%08s",h);
    printf("i=%d,hs=%s
",i,hs);
// 十六进制字符串转成十进制数
    strcpy(hs,"00000400");
    sscanf(hs,"%x",&i);
    printf("hs=%s,i=%d
",hs,i);
// 二进制字符串转化为十六进制字符串；
    strcpy(bs,"00000000000000000000010000000000");
    i=strtol(bs,&e,2);
    ltoa(i,h,16);
    sprintf(hs,"%08s",h);
    printf("bs=%s,hs=%s
",bs,hs);
// 二进制字符串转化为十进制数；
    strcpy(bs,"00000000000000000000010000000000");
    i=strtol(bs,&e,2);
    printf("bs=%s,i=%d
",bs,i);
// 十六进制字符串转成二进制串
    strcpy(hs,"00000400");
    sscanf(hs,"%x",&i);
    ltoa(i,b,2);
    sprintf(bs,"%032s",b);
    printf("hs=%s,bs=%s
",hs,bs);
// ASCGBK字符串转十六进制串
    strcpy(s,"a汉");
    i=0;
    while (1) {
        if (0==s[i]) break;
        sprintf(hs+i*2,"%02X",(unsigned char)s[i]);
        i++;
    }
    setlocale(LC_ALL,"chs");
    printf("s=%s,hs=%s
",s,hs); 

// 十六进制字符串转成汉字（GBK）及字符(ASC)
    strcpy(hs,"61BABA");
    i=0;
    while (1) {
        if (1!=sscanf(hs+i*2,"%2x",&v)) break;
        s[i]=(char)v;
        i++;
    }
    s[i]=0;
    printf("hs=%s,s=%s
",hs,s);

    return 0;

}
//i=1024,bs=00000000000000000000010000000000
//i=1024,hs=00000400
//hs=00000400,i=1024
//bs=00000000000000000000010000000000,hs=00000400
//bs=00000000000000000000010000000000,i=1024
//hs=00000400,bs=00000000000000000000010000000000
//s=a汉,hs=61BABA
//hs=61BABA,s=a汉


------解决方式--------------------


#include <stdio.h>

union decompose{
	int integer;

	struct{
		unsigned int hex0 : 4;
		unsigned int hex1 : 4;
		unsigned int hex2 : 4;
		unsigned int hex3 : 4;
		unsigned int hex4 : 4;
		unsigned int hex5 : 4;
		unsigned int hex6 : 4;
		unsigned int hex7 : 4;
	}hex4;

};
/* 此宏定义不能用于循环，即n不能是变量，仅仅能是数字
 * 因此比較适用与零散获取位状态或者字节状态
 */

#define GETHEX(x, n) (((union decompose){.integer = x}).hex4.hex##n) 

void test_getx(int tmp)
{
	printf("%X", GETHEX(tmp, 0));
	printf("%X", GETHEX(tmp, 1));
	printf("%X", GETHEX(tmp, 2));
	printf("%X", GETHEX(tmp, 3));
	printf("%X", GETHEX(tmp, 4));
	printf("%X", GETHEX(tmp, 5));
	printf("%X", GETHEX(tmp, 6));
	printf("%X
", GETHEX(tmp, 7));

}

int main()
{
	test_getx(100);	
	return 0;
}

MFC 16进制转2进制

16 转到10

//16转10进制
int CCIecClientSimulator12Dlg::HexToDec( char *s )
{
	char *p = s;

	//空串返回0。
	if(*p == '')
		return 0;

	//忽略开头的'0'字符
	while(*p == '0')
		p++;

	int dec = 0;
	char c;

	//循环直到字符串结束。
	while(c = *p++)
	{
		//dec乘16
		dec <<= 4;

		//数字字符。
		if(c >= '0' && c <= '9')
		{
			dec += c - '0';
			continue;
		}

		//小写abcdef。
		if(c >= 'a' && c <= 'f')
		{
			dec += c - 'a' + 10;
			continue;
		}

		//大写ABCDEF。
		if(c >= 'A' && c <= 'F')
		{
			dec += c - 'A' + 10;
			continue;
		}

		//没有从不论什么一个if语句中结束，说明遇到了非法字符。
		return -1;
	}
	//正常结束循环，返回10进制整数值。
	return dec;
}

10 转到2 

UINT CCIecClientSimulator12Dlg::to2( int n )
{
	int r=0;
	//double r=0;
	double b =10;
	int shang,yushu;
	shang=n;
	int i=0;
	while(shang!=0)
	{
		yushu=shang%2;
		r=r+pow(b,i)*yushu;
		i++;
		shang=shang/2;
	}
	return r;
}