用c语言写一个函数把十进制转换成十六进制解决方案

用c语言写一个函数把十进制转换成十六进制
用c语言写一个函数把十进制转换成十六进制
网上找到一些，感觉有占乱
------解决方案--------------------

#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\n",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\n",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\n",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\n",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\n",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\n",hs,bs);

// ASC\GBK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\n",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\n",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

------解决方案--------------------

#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，只能是数字

 * 因此比较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\n", GETHEX(tmp, 7));


}


int main()

{

	test_getx(100);	

	return 0;

}