#include <winsock.h>
#pragma comment(lib, "Ws2_32.lib")//将一个8位数高低4位交换
static unsigned char bswap_8(unsigned char v)
{return ((v & 0xff) << 4) | (v >> 4); //将参数(v & 0xff) << 4 相当于放到高位， v >> 4 位相当于放在低位
}//将一个16位数高低8位交换
static unsigned short bswap_16(unsigned short v)
{return ((v & 0xff) << 8) | (v >> 8);
}//将一个32位数高低16位交换
static unsigned int bswap_32(unsigned int v)
{return ((v & 0xff) << 24) | ((v & 0xff00) << 8) |((v & 0xff0000) >> 8) | (v >> 24);
}enum DataByteOrder
{ABCD,DCBA,BADC,CDAB
};float get_float_databyteorder(const uint16_t *src, DataByteOrder order)
{float f = 0;uint32_t i;switch (order){case ABCD:i = ntohl(((uint32_t)src[0] << 16) + src[1]);memcpy(&f, &i, sizeof(float));break;case DCBA:i = ntohl(bswap_32((((uint32_t)src[0]) << 16) + src[1]));memcpy(&f, &i, sizeof(float));break;case BADC:i = ntohl((uint32_t)(bswap_16(src[0]) << 16) + bswap_16(src[1]));memcpy(&f, &i, sizeof(float));break;case CDAB:i = ntohl((((uint32_t)src[1]) << 16) + src[0]);memcpy(&f, &i, sizeof(float));break;default:break;}return f;
}void set_float_databyteorder(float f, DataByteOrder order, uint16_t *dest)
{uint32_t i;switch (order){case ABCD:memcpy(&i, &f, sizeof(uint32_t));i = htonl(i);dest[0] = (uint16_t)(i >> 16);dest[1] = (uint16_t)i;break;case DCBA:memcpy(&i, &f, sizeof(uint32_t));i = bswap_32(htonl(i));dest[0] = (uint16_t)(i >> 16);dest[1] = (uint16_t)i;break;case BADC:memcpy(&i, &f, sizeof(uint32_t));i = htonl(i);dest[0] = (uint16_t)bswap_16(i >> 16);dest[1] = (uint16_t)bswap_16(i & 0xFFFF);break;case CDAB:memcpy(&i, &f, sizeof(uint32_t));i = htonl(i);dest[0] = (uint16_t)i;dest[1] = (uint16_t)(i >> 16);break;default:break;}
}int main(int argc, char *argv[])
{float f1 = 12.34;uint16_t dst[2];set_float_databyteorder(f1, ABCD, dst);float f2 = get_float_databyteorder(dst, ABCD);return 0;
}