高分求助！Unsigned long int 如何转换为 Unsigned Char[4]。高位在前！

[zl198183]

Unsigned long int 如何转换为 Unsigned Char[4]。高位在前！

[过客猫2022]

用共用体union
union v
{
unsigned long int un;
char uc[4];
};

v.un = 12345678;
这样v.uc即呆转换后的数据

[jacknes009]

用移位的方法也可以哦，
p[3] = a & 0xff;
p[2] = (a >> 8) & 0xff;
p[1] = (a >> 16) & 0xff;
p[0] = (a >> 24) & 0xff;

[玄之丞]

shadowstar 正解

[i_love_pc]

memcpy
要转换顺序就用数组排序

[fjye]

#include <winsock2.h>


char p[4]={0};
u_long a;
a = 12345678;
memcpy(p,&a,4);//原顺序
a = htonl(12345678);
memcpy(p,&a,4);//高位在前的网络字节序

[shadowstar]

unsigned long int un;
unsigned char uc[4];
unsigned char* p;

p = (unsigned char*)&un;
uc[0] = p[3];
uc[1] = p[2];
uc[2] = p[1];
uc[3] = p[0];

[FengSC]

(unsigned char*)&