通过特定获取获取电脑外网IP地址

void  get_WanIp()
{

char Buf_File_Read[MAX_PATH] = {0};
char IP_Temp[128];
char IP_Host[64];
int Result_URLDownloadToFile = 1;
char szFilePath[MAX_PATH] = {0};
GetTempPathA(MAX_PATH,szFilePath);
strcat(szFilePath,"IPinTheWorld.ini");

Result_URLDownloadToFile = URLDownloadToFileA(0,"http://ip.dnsexit.com/index.php",szFilePath,0,NULL);
if(Result_URLDownloadToFile != 0)//若URLDownloadToFile()成功，返回0
{
MessageBox(NULL, "网络故障，无法接入Internet，请联系网络管理员","提示",MB_ICONASTERISK);
return ;
}

FILE *fp_Download_URL_File=NULL;
if ((fp_Download_URL_File=fopen( szFilePath,"r")) == NULL)
{
MessageBox(NULL, "系统故障，无法打开IP文件，请检查防火墙设置或联系管理人员","提示",MB_ICONASTERISK);
return ;
}

if ( fp_Download_URL_File != NULL )
{
fseek(fp_Download_URL_File, 0, SEEK_SET);
fread(Buf_File_Read,1,256,fp_Download_URL_File);
fclose(fp_Download_URL_File);
DeleteFile(szFilePath);
}
strcpy(g_szWanIp,Buf_File_Read);
}