ip地址转换： char * <---> unsigned int

       仅做记录：

 

#include
#include
#include
#include 
#include 
#include 
using namespace std;

int main()
{
	char szIP[32] = "10.172.18.18";
	unsigned int ulIP1 = htonl(inet_addr(szIP));
	cout << ulIP1 << endl;

	unsigned int ulIP2 = htonl(ulIP1);
	string resultIP=inet_ntoa(*(in_addr*)(&ulIP2));
	cout << resultIP << endl;

	return 0;
}

     结果：

 

179048978
10.172.18.18

 

     有时候如果忘了大小端字节序， 就容易出错， 如转成了18.18.172.10.

 

     再来看下：

 

#include    
#include    
using namespace std;

string uiIP2Str(unsigned int uiIP, bool bNetByteOrder = true)
{
    char szIP[16] = {0};
    unsigned char *c = (unsigned char *)&uiIP;
    if(bNetByteOrder)
    {
        snprintf(szIP, sizeof(szIP), "%hhu.%hhu.%hhu.%hhu", *c, *(c+1), *(c+2), *(c+3));
    }
    else
    {
        snprintf(szIP, sizeof(szIP), "%hhu.%hhu.%hhu.%hhu", *(c+3), *(c+2), *(c+1), *c);
    }
	
    return string(szIP);
}

int main()
{
	unsigned int uiIP = 179048978;
	cout << uiIP2Str(uiIP, false) << endl;

    return 0;
}

       结果：10.172.18.18