if ( result.IndexOf ( "." ) == -1 ) //没有"."肯定是非IPv4格式
result = null;
else
{
if ( result.IndexOf ( "," ) != -1 )
{
//有","，估计多个代理。取第一个不是内网的IP。
result = result.Replace ( " ", "" ).Replace ( "", "" );
string[] temparyip = result.Split ( ",;".ToCharArray() );
for ( int i = 0; i < temparyip.Length; i++ )
{
if ( IsIPAddress ( temparyip[i] )
&& temparyip[i].Substring ( 0, 3 ) != "10."
&& temparyip[i].Substring ( 0, 7 ) != "192.168"
&& temparyip[i].Substring ( 0, 7 ) != "172.16." )
{
