/// <summary>
/// Parse the hosts file and get all the entries.
/// </summary>
/// <returns>Collection of hosts file entries</returns>
public static GetHostFileEntriesResult GetHostFileEntries(string hostsFilePath = @"C:\Windows\System32\drivers\etc\hosts")
{
var result = new GetHostFileEntriesResult();
if (!File.Exists(hostsFilePath))
{
var ex = new FileNotFoundException("Hosts file was not found!", hostsFilePath);
result.AddException(ex);
return result;
}
var allLines = File.ReadAllLines(hostsFilePath);
for(int i=0; i < allLines.Count(); i++)
{
var line = allLines[i].Trim();
// Skip blank lines
if (string.IsNullOrWhiteSpace(line))
{
continue;
}
var match = _dnsHostEntryRowPattern.Match(line);
if (!match.Success)
{
var ex = new FormatException(string.Format("line {0:000} was not formatted as expected. Skipping.", i+1));
result.AddException(ex);
continue;
}
bool enabled = false;
string ipAddressString = string.Empty;
string hostNames = string.Empty;
string comment = string.Empty;
bool hidden = false;
enabled = line[0] != '#';
ipAddressString = match.Groups["ip"].Value.Trim();
hostNames = match.Groups["hosts"].Value.Trim();
comment = match.Groups["comment"].Value.Trim();
// Skip invalid IP address
IPAddress ipAddress;
if (!System.Net.IPAddress.TryParse(ipAddressString, out ipAddress))
{
var ex = new FormatException(string.Format("line {0:000} did not have a valid IP address. Skipping.", i+1));
result.AddException(ex);
continue;
}
// Comment
if (!String.IsNullOrEmpty(comment))
{
hidden = comment[0] == '!';
if (hidden)
{
comment = comment.Substring(1).Trim();
}
}
DnsHostEntry entry = null;
var hosts = hostNames.Split(" ".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
foreach (var host in hosts)
{
try
{
var ub = new UriBuilder(System.Uri.UriSchemeHttp.ToString(), host);
entry = new DnsHostEntry(ub.Uri, ipAddress);
entry.Enabled = enabled;
entry.Comment = comment;
entry.IsInHostsFile = true;
result.AddEntry(entry);
}
catch (Exception ex)
{
var fex = new FormatException(string.Format(@"line {0:000} did not have a valid IP address. Skipping. Full error message:\r\n\{1}", i + 1, ex.GetAllExceptionsString()));
result.AddException(fex);
}
}
}
return result;
}
public void AddEntry(DnsHostEntry entry)
{
_entries.Add(entry);
}
public void AddException(DnsHostEntry binding, BindingAction action, Exception ex)
{
string message = string.Format("Error while {0} binding \"{1}\" to website \"{2}\"", action, binding.DnsSafeDisplayString, binding.Website.Name);
var newEx = new Exception(message, ex);
_exceptions.Add(newEx);
}
