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发送端： 将浮点数转换为字节数组

float floatNum;
unsigned char byteArry[sizeof(double)];    
void Float2Byte(float floatNum, unsigned char* byteArry) {
   
   
    char* pchar = (char*)&floatNum;
    for (int i = 0; i < sizeof(float); i++) {
   
   
        *byteArry = *pchar