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I need to parse this string from serial:-
!00037,00055#
00037 as one string, 00055 as another string
However this string is came out when the robot's tire is rotated and some other string may also display before and after the string that I need to parse. For example this is the some of the transmission received:-
11,00085#R-STOPR-STOP!00011,00095#!00001,00015#R-STOP!00001,00085#!00003,00075#!00006,00015#R-STOP!00009,00025#!00011,00035#!00011,00085#R-STOPR-STOP!00011,00095#!00001,00015#R-STOP!00001,00085#!00003,00075#!00006,00015#R-STOP!00009,00025#!00011,00035#R-STOP!00001,00085#!00003,00075#!00006,00015#R-STOP!00009,00025#!00011,00035#R-STOP!00037,00055#!00023,00075#R-STOPR-STOP!00022,00065#!00011,00085#R-STOPR-STOP!00011,00095#!00001,00015#R-STOP!00001,00085#!00003,00075#!00006,00015#R-STOP!00009,00025#!00011,00035#R-STOP!00037,00055#!00023,00075#R-STOPR-STOP!00022,00065#!00011,00085#R-STOPR-STOP!00011,00095#!00001,00015#
So far I'm stuck at what to do next after SerialPort.ReadExisting()
Here is some code to retrieve the serial data:-
private void serialCom_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
try
{
InputData = serialCom.ReadExisting();
if (InputData != String.Empty)
{
this.BeginInvoke(new SetTextCallback(IncomingData), new object[] { InputData });
}
}
catch
{
MessageBox.Show("Error");
}
}
and display incoming serial data inside textbox
private void IncomingData(string data)
{
tb_incomingData.AppendText(data);
tb_incomingData.ScrollToCaret();
}
This code is using .NET Framework 4.0 and Windows Form.
Finally solve it using indexof and substring.
private void IncomingData(string data)
{
//Show received data in textbox
tb_incomingData.AppendText(data);
tb_incomingData.ScrollToCaret();
//Append data inside longdata (string)
longData = longData + data;
if (longData.Contains('#') && longData.Contains(',') && longData.Contains('!'))
{
try
{
indexSeru = longData.IndexOf('!'); //retrieve index number of the symbol !
indexComma = longData.IndexOf(','); //retrieve index number of the symbol ,
indexAlias = longData.IndexOf('#'); //retrieve index number of the symbol ,
rotation = longData.Substring(indexSeru + 1, 5); //first string is taken after symbol ! and 5 next char
subRotation = longData.Substring(indexComma + 1, 5); //second string is taken after symbol ! and 5 next char
//tss_distance.Text = rotation + "," + subRotation;
longData = null; //clear longdata string
}
catch
{
indexSeru = 0;
indexComma = 0;
indexAlias = 0;
}
}
}
You can determine your pattern to transform this string into a array using SPLIT function.
This code, send "!00037,00055#" returns two itens: 00037 and 00055.
static void Main(string[] args)
{
string k = "!00037,00055#";
var array = k.ToString().Split(',');
Console.WriteLine("Dirty Itens");
for (var x = 0; x <= array.Length - 1; x++)
{
var linha = "Item " + x.ToString() + " = " + array[x];
Console.WriteLine(linha);
}
Console.WriteLine("Cleaned Itens");
for (var x = 0; x <= array.Length - 1; x++)
{
var linha = "Item " + x.ToString() + " = " + CleanString(array[x]);
Console.WriteLine(linha);
}
Console.ReadLine();
}
public static string CleanString(string inputString)
{
string resultString = "";
Regex regexObj = new Regex(#"[^\d]");
resultString = regexObj.Replace(inputString, "");
return resultString;
}
For example if I have...
string a = "personil";
string b = "personal";
I would like to get...
string c = "person[i]l";
However it is not necessarily a single character. I could be like this too...
string a = "disfuncshunal";
string b = "dysfunctional";
For this case I would want to get...
string c = "d[isfuncshu]nal";
Another example would be... (Notice that the length of both words are different.)
string a = "parralele";
string b = "parallel";
string c = "par[ralele]";
Another example would be...
string a = "ato";
string b = "auto";
string c = "a[]to";
How would I go about doing this?
Edit: The length of the two strings can be different.
Edit: Added additional examples. Credit goes to user Nenad for asking.
I must be very bored today, but I actually made UnitTest that pass all 4 cases (if you did not add some more in the meantime).
Edit: Added 2 edge cases and fix for them.
Edit2: letters that repeat multiple times (and error on those letters)
[Test]
[TestCase("parralele", "parallel", "par[ralele]")]
[TestCase("personil", "personal", "person[i]l")]
[TestCase("disfuncshunal", "dysfunctional", "d[isfuncshu]nal")]
[TestCase("ato", "auto", "a[]to")]
[TestCase("inactioned", "inaction", "inaction[ed]")]
[TestCase("refraction", "fraction", "[re]fraction")]
[TestCase("adiction", "ad[]diction", "ad[]iction")]
public void CompareStringsTest(string attempted, string correct, string expectedResult)
{
int first = -1, last = -1;
string result = null;
int shorterLength = (attempted.Length < correct.Length ? attempted.Length : correct.Length);
// First - [
for (int i = 0; i < shorterLength; i++)
{
if (correct[i] != attempted[i])
{
first = i;
break;
}
}
// Last - ]
var a = correct.Reverse().ToArray();
var b = attempted.Reverse().ToArray();
for (int i = 0; i < shorterLength; i++)
{
if (a[i] != b[i])
{
last = i;
break;
}
}
if (first == -1 && last == -1)
result = attempted;
else
{
var sb = new StringBuilder();
if (first == -1)
first = shorterLength;
if (last == -1)
last = shorterLength;
// If same letter repeats multiple times (ex: addition)
// and error is on that letter, we have to trim trail.
if (first + last > shorterLength)
last = shorterLength - first;
if (first > 0)
sb.Append(attempted.Substring(0, first));
sb.Append("[");
if (last > -1 && last + first < attempted.Length)
sb.Append(attempted.Substring(first, attempted.Length - last - first));
sb.Append("]");
if (last > 0)
sb.Append(attempted.Substring(attempted.Length - last, last));
result = sb.ToString();
}
Assert.AreEqual(expectedResult, result);
}
Have you tried my DiffLib?
With that library, and the following code (running in LINQPad):
void Main()
{
string a = "disfuncshunal";
string b = "dysfunctional";
var diff = new Diff<char>(a, b);
var result = new StringBuilder();
int index1 = 0;
int index2 = 0;
foreach (var part in diff)
{
if (part.Equal)
result.Append(a.Substring(index1, part.Length1));
else
result.Append("[" + a.Substring(index1, part.Length1) + "]");
index1 += part.Length1;
index2 += part.Length2;
}
result.ToString().Dump();
}
You get this output:
d[i]sfunc[shu]nal
To be honest I don't understand what this gives you, as you seem to completely ignore the changed parts in the b string, only dumping the relevant portions of the a string.
Here is a complete and working console application that will work for both examples you gave:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApplication2
{
class Program
{
static void Main(string[] args)
{
string a = "disfuncshunal";
string b = "dysfunctional";
StringBuilder sb = new StringBuilder();
for (int i = 0; i < a.Length; i++)
{
if (a[i] != b[i])
{
sb.Append("[");
sb.Append(a[i]);
sb.Append("]");
continue;
}
sb.Append(a[i]);
}
var str = sb.ToString();
var startIndex = str.IndexOf("[");
var endIndex = str.LastIndexOf("]");
var start = str.Substring(0, startIndex + 1);
var mid = str.Substring(startIndex + 1, endIndex - 1);
var end = str.Substring(endIndex);
Console.WriteLine(start + mid.Replace("[", "").Replace("]", "") + end);
}
}
}
it will not work if you want to display more than one entire section of the mismatched word.
You did not specify what to do if the strings were of different lengths, but here is a solution to the problem when the strings are of equal length:
private string Compare(string string1, string string2) {
//This only works if the two strings are the same length..
string output = "";
bool mismatch = false;
for (int i = 0; i < string1.Length; i++) {
char c1 = string1[i];
char c2 = string2[i];
if (c1 == c2) {
if (mismatch) {
output += "]" + c1;
mismatch = false;
} else {
output += c1;
}
} else {
if (mismatch) {
output += c1;
} else {
output += "[" + c1;
mismatch = true;
}
}
}
return output;
}
Not really good approach but as an exercise in using LINQ: task seem to be find matching prefix and suffix for 2 strings, return "prefix + [+ middle of first string + suffix.
So you can match prefix (Zip + TakeWhile(a==b)), than repeat the same for suffix by reversing both strings and reversing result.
var first = "disfuncshunal";
var second = "dysfunctional";
// Prefix
var zipped = first.ToCharArray().Zip(second.ToCharArray(), (f,s)=> new {f,s});
var prefix = string.Join("",
zipped.TakeWhile(c => c.f==c.s).Select(c => c.f));
// Suffix
var zippedReverse = first.ToCharArray().Reverse()
.Zip(second.ToCharArray().Reverse(), (f,s)=> new {f,s});
var suffix = string.Join("",
zippedReverse.TakeWhile(c => c.f==c.s).Reverse().Select(c => c.f));
// Cut and combine.
var middle = first.Substring(prefix.Length,
first.Length - prefix.Length - suffix.Length);
var result = prefix + "[" + middle + "]" + suffix;
Much easier and faster approach is to use 2 for loops (from start to end, and from end to start).
I wish to implement a fairly simple CSV checker in my C#/ASP.NET application - my project automatically generates CSV's from GridView's for users, but I want to be able to quickly run through each line and see if they have the same amount of commas, and throw an exception if any differences occur. So far I have this, which does work but there are some issues I'll describe soon:
int? CommaCount = null;
StringBuilder sb = new StringBuilder();
StringWriter sw = new StringWriter(sb);
String Str = null;
//This loops through all the headerrow cells and writes them to the stringbuilder
for (int k = 0; k <= (grd.Columns.Count - 1); k++)
{
sw.Write(grd.HeaderRow.Cells[k].Text + ",");
}
sw.WriteLine(",");
//This loops through all the main rows and writes them to the stringbuilder
for (int i = 0; i <= grd.Rows.Count - 1; i++)
{
StringBuilder RowString = new StringBuilder();
for (int j = 0; j <= grd.Columns.Count - 1; j++)
{
//We'll need to strip meaningless junk such as <br /> and
Str = grd.Rows[i].Cells[j].Text.ToString().Replace("<br />", "");
if (Str == " ")
{
Str = "";
}
Str = "\"" + Str + "\"" + ",";
RowString.Append(Str);
sw.Write(Str);
}
sw.WriteLine();
//The below code block ensures that each row contains the same number of commas, which is crucial
int RowCommaCount = CheckChar(RowString.ToString(), ',');
if (CommaCount == null)
{
CommaCount = RowCommaCount;
}
else
{
if (CommaCount!= RowCommaCount)
{
throw new Exception("CSV generated is corrupt - line " + i + " has " + RowCommaCount + " commas when it should have " + CommaCount);
}
}
}
sw.Close();
And my CheckChar method:
protected static int CheckChar(string Input, char CharToCheck)
{
int Counter = 0;
foreach (char StringChar in Input)
{
if (StringChar == CharToCheck)
{
Counter++;
}
}
return Counter;
}
Now my problem is, if a cell in the grid contains a comma, my check char method will still count these as delimiters so will return an error. As you can see in the code, I wrap all the values in " characters to 'escape' them. How simple would it be to ignore commas in values in my method? I assume I'll need to rewrite the method quite a lot.
var rx = new Regex("^ ( ( \"[^\"]*\" ) | ( (?!$)[^\",] )+ | (?<1>,) )* $", RegexOptions.ExplicitCapture | RegexOptions.IgnorePatternWhitespace | RegexOptions.Multiline);
var matches = rx.Matches("Hello,World,How,Are\nYou,Today,This,Is,\"A beautiful, world\",Hi!");
for (int i = 1; i < matches.Count; i++) {
if (matches[i].Groups[1].Captures.Count != matches[i - 1].Groups[1].Captures.Count) {
throw new Exception();
}
}
You could just use a regular expression that matches one item and count the number of matches in your line. An example of such a regex is the following:
var itemsRegex =
new Regex(#"(?<=(^|[\" + separator + #"]))((?<item>[^""\" + separator +
#"\n]*)|(?<item>""([^""]|"""")*""))(?=($|[\" + separator + #"]))");
Just do something like the following (assuming you don't want to have " inside your fields (otherwise these need some extra handling)):
protected static int CheckChar(string Input, char CharToCheck, char fieldDelimiter)
{
int Counter = 0;
bool inValue = false;
foreach (char StringChar in Input)
{
if (StringChar == fieldDelimiter)
inValue = !inValue;
else if (!inValue && StringChar == CharToCheck)
Counter++;
}
return Counter;
}
This will cause inValue to be true while inside fields. E.g. pass '"' as fieldDelimiter to ignore everything between "...". Just note that this won't handle escaped " (like "" or \"). You'd have to add such handling yourself.
Instead of checking the resulting string (the cake) you should check the fields (ingredients) before you concatenate (mix) them. That would give you the change to do something constructive (escaping/replacing) and throwing an exception only as a last resort.
In general, "," are legal in .csv fields, as long as the string fields are quoted. So internal "," should not be a problem, but the quotes may well be.
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Is there any built in method in the .NET library that will return all of the MX records for a given domain? I see how you get CNAMES, but not MX records.
Update 2018/5/23:
Check out MichaC's answer for a newer library that has .NET standard support.
Original Answer:
The ARSoft.Tools.Net library by Alexander Reinert seems to do the job pretty well.
It's available from NuGet:
PM> Install-Package ARSoft.Tools.Net
Import the namespace:
using ARSoft.Tools.Net.Dns;
Then making a synchronous lookup is as simple as:
var resolver = new DnsStubResolver();
var records = resolver.Resolve<MxRecord>("gmail.com", RecordType.Mx);
foreach (var record in records) {
Console.WriteLine(record.ExchangeDomainName?.ToString());
}
Which gives us the output:
gmail-smtp-in.l.google.com.
alt1.gmail-smtp-in.l.google.com.
alt2.gmail-smtp-in.l.google.com.
alt3.gmail-smtp-in.l.google.com.
alt4.gmail-smtp-in.l.google.com.
Underneath the hood, it looks like the library constructs the UDP (or TCP) packets necessary to send to the resolver, like you might expect. The library even has logic (invoked with DnsClient.Default) to discover which DNS server to query.
Full documentation can be found here.
Just roled my own library because there was nothing for .net core / xplat support... https://github.com/MichaCo/DnsClient.NET
It works pretty great and gives you dig like log messages if you want.
Simple to use
var lookup = new LookupClient();
var result = await lookup.QueryAsync("google.com", QueryType.ANY);
and works with custom servers running on any ports, multiple servers, etc...
see also DnsClient Website for more details
I spent all day figuring out how to send/receive dns requests and came up with this. Its a complete generic handler. You just have to set the dns server and pass in 'd' eg. my.website.com?d=itmanx.com
<%# WebHandler Language="C#" Class="Handler" %>
using System;
using System.Web;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Collections.Generic;
public class Handler : IHttpHandler
{
string dns = "dc1"; //change to your dns
string qtype = "15"; //A=1 MX=15
string domain = "";
int[] resp;
public void ProcessRequest(HttpContext context)
{
context.Response.ContentType = "text/plain";
try
{
if (context.Request["t"] != null) qtype = context.Request["t"];
if (context.Request["d"] != null) domain = context.Request["d"];
if (string.IsNullOrEmpty(domain)) throw new Exception("Add ?d=<domain name> to url or post data");
Do(context);
}
catch (Exception ex)
{
string msg = ex.Message;
if (msg == "1") msg = "Malformed packet";
else if (msg == "5") msg = "Refused";
else if (msg == "131") msg = "No such name";
context.Response.Write("Error: " + msg);
}
}
public void Do(HttpContext context)
{
UdpClient udpc = new UdpClient(dns, 53);
// SEND REQUEST--------------------
List<byte> list = new List<byte>();
list.AddRange(new byte[] { 88, 89, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0 });
string[] tmp = domain.Split('.');
foreach (string s in tmp)
{
list.Add(Convert.ToByte(s.Length));
char[] chars = s.ToCharArray();
foreach (char c in chars)
list.Add(Convert.ToByte(Convert.ToInt32(c)));
}
list.AddRange(new byte[] { 0, 0, Convert.ToByte(qtype), 0, 1 });
byte[] req = new byte[list.Count];
for (int i = 0; i < list.Count; i++) { req[i] = list[i]; }
udpc.Send(req, req.Length);
// RECEIVE RESPONSE--------------
IPEndPoint ep = null;
byte[] recv = udpc.Receive(ref ep);
udpc.Close();
resp = new int[recv.Length];
for (int i = 0; i < resp.Length; i++)
resp[i] = Convert.ToInt32(recv[i]);
int status = resp[3];
if (status != 128) throw new Exception(string.Format("{0}", status));
int answers = resp[7];
if (answers == 0) throw new Exception("No results");
int pos = domain.Length + 18;
if (qtype == "15") // MX record
{
while (answers > 0)
{
int preference = resp[pos + 13];
pos += 14; //offset
string str = GetMXRecord(pos, out pos);
context.Response.Write(string.Format("{0}: {1}\n", preference, str));
answers--;
}
}
else if (qtype == "1") // A record
{
while (answers > 0)
{
pos += 11; //offset
string str = GetARecord(ref pos);
context.Response.Write(string.Format("{0}\n", str));
answers--;
}
}
}
//------------------------------------------------------
private string GetARecord(ref int start)
{
StringBuilder sb = new StringBuilder();
int len = resp[start];
for (int i = start; i < start + len; i++)
{
if (sb.Length > 0) sb.Append(".");
sb.Append(resp[i + 1]);
}
start += len + 1;
return sb.ToString();
}
private string GetMXRecord(int start, out int pos)
{
StringBuilder sb = new StringBuilder();
int len = resp[start];
while (len > 0)
{
if (len != 192)
{
if (sb.Length > 0) sb.Append(".");
for (int i = start; i < start + len; i++)
sb.Append(Convert.ToChar(resp[i + 1]));
start += len + 1;
len = resp[start];
}
if (len == 192)
{
int newpos = resp[start + 1];
if (sb.Length > 0) sb.Append(".");
sb.Append(GetMXRecord(newpos, out newpos));
start++;
break;
}
}
pos = start + 1;
return sb.ToString();
}
//------------------------------------------------------
public bool IsReusable { get { return false; } }
}
My approach was to use nslookup.exe to retreive the MX record.
The solution is not as fancy as rewriting whole DNS or using a System DLL -> but it works, with a little amount of lines.
To get things right, this code >just works< it's not ressource efficient nor fast and has a lots of room for improvment (multiple hostnames, async, more usefull return value,adding the priority):
static List<string> GetMxRecords(string host){
ProcessStartInfo nslookup_config = new ProcessStartInfo("nslookup.exe");
nslookup_config.RedirectStandardInput = true;
nslookup_config.RedirectStandardOutput = true;
nslookup_config.RedirectStandardError = true;
nslookup_config.UseShellExecute = false;
var nslookup = Process.Start(nslookup_config);
nslookup.StandardInput.WriteLine("set q=mx");
nslookup.StandardInput.WriteLine(host);
nslookup.StandardInput.WriteLine("exit");
List<string> lines = new List<string>();
while (!nslookup.StandardOutput.EndOfStream)
{
string l = nslookup.StandardOutput.ReadLine();
if (l.Contains("internet address ="))
{
while (l.Contains("\t\t"))
{
l = l.Replace("\t\t", "\t");
}
lines.Add(l.Replace("\tinternet address = ","="));
}
}
nslookup.Close();
return lines;
}
Should be working international, since nslookup does not support any translation (I'm working on a German machine and I'm getting english output).
The result are strings like this:
alt4.gmail-smtp-in.l.google.com=74.125.28.27
alt2.gmail-smtp-in.l.google.com=74.125.200.27
alt1.gmail-smtp-in.l.google.com=209.85.233.26
gmail-smtp-in.l.google.com=66.102.1.27
alt3.gmail-smtp-in.l.google.com=108.177.97.27
The accepted answer doesn't work for .NET framework < 4.5, so would suggest that those of you who can't use ARSOFT.Tools can use DNDNs from https://dndns.codeplex.com
Given below is a console application that returns the MX record for a given domain modifying their examples.
using System;
using System.Net.Sockets;
using DnDns.Enums;
using DnDns.Query;
using DnDns.Records;
namespace DnDnsExamples
{
class Program
{
static void Main(string[] args)
{
DnsQueryRequest request3 = new DnsQueryRequest();
DnsQueryResponse response3 = request3.Resolve("gmail.com", NsType.MX, NsClass.INET, ProtocolType.Tcp);
OutputResults(response3);
Console.ReadLine();
}
private static void OutputResults(DnsQueryResponse response)
{
foreach (IDnsRecord record in response.Answers)
{
Console.WriteLine(record.Answer);
Console.WriteLine(" |--- RDATA Field Length: " + record.DnsHeader.DataLength);
Console.WriteLine(" |--- Name: " + record.DnsHeader.Name);
Console.WriteLine(" |--- NS Class: " + record.DnsHeader.NsClass);
Console.WriteLine(" |--- NS Type: " + record.DnsHeader.NsType);
Console.WriteLine(" |--- TTL: " + record.DnsHeader.TimeToLive);
Console.WriteLine();
}
}
}
}
Here is a Class I use to look up MX records only.
using System;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Collections.Specialized;
namespace Mx.Dns
{
public class Query
{
//Build a DNS query buffer according to RFC 1035 4.1.1 e 4.1.2
private readonly int id;
private readonly int flags;
private readonly int QDcount;
private readonly int ANcount;
private readonly int NScount;
private readonly int ARcount;
private readonly string Qname;
private readonly int Qtype;
private readonly int Qclass;
public byte[] buf;
public Query(int ID, string query, int qtype)
{
//init vectors with given + default values
id = ID;
flags = 256;
QDcount = 1;
ANcount = 0;
NScount = 0;
ARcount = 0;
Qname = query;
Qtype = qtype;
Qclass = 1; //Internet = IN = 1
//build a buffer with formatted query data
//header information (16 bit padding
buf = new byte[12 + Qname.Length + 2 + 4];
buf[0] = (byte)(id / 256);
buf[1] = (byte)(id - (buf[0] * 256));
buf[2] = (byte)(flags / 256);
buf[3] = (byte)(flags - (buf[2] * 256));
buf[4] = (byte)(QDcount / 256);
buf[5] = (byte)(QDcount - (buf[4] * 256));
buf[6] = (byte)(ANcount / 256);
buf[7] = (byte)(ANcount - (buf[6] * 256));
buf[8] = (byte)(NScount / 256);
buf[9] = (byte)(NScount - (buf[8] * 256));
buf[10] = (byte)(ARcount / 256);
buf[11] = (byte)(ARcount - (buf[10] * 256));
//QNAME (RFC 1035 4.1.2)
//no padding
string[] s = Qname.Split('.');
int index = 12;
foreach (string str in s) {
buf[index] = (byte)str.Length;
index++;
byte[] buf1 = Encoding.ASCII.GetBytes(str);
buf1.CopyTo(buf, index);
index += buf1.Length;
}
//add root domain label (chr(0))
buf[index] = 0;
//add Qtype and Qclass (16 bit values)
index = buf.Length - 4;
buf[index] = (byte)(Qtype / 256);
buf[index + 1] = (byte)(Qtype - (buf[index] * 256));
buf[index + 2] = (byte)(Qclass / 256);
buf[index + 3] = (byte)(Qclass - (buf[index + 2] * 256));
}
}
public class C_DNSquery
{
public StringCollection result = new StringCollection();
public int Error = 0;
public string ErrorTxt = "undefined text";
public bool Done = false;
public UdpClient udpClient;
private string DNS;
private string Query;
private int Qtype;
public bool IS_BLACKLIST_QUERY = false;
public C_DNSquery(string IPorDNSname, string query, int type)
{
DNS = IPorDNSname;
Query = query;
Qtype = type;
}
public void doTheJob()
{
//check if provided DNS contains an IP address or a name
IPAddress ipDNS;
IPHostEntry he;
try {
//try to parse an IPaddress
ipDNS = IPAddress.Parse(DNS);
} catch (FormatException ) {
// Console.WriteLine(e);
//format error, probably is a FQname, try to resolve it
try {
//try to resolve the hostname
he = Dns.GetHostEntry(DNS);
} catch {
//Error, invalid server name or address
Error = 98;
ErrorTxt = "Invalid server name:" + DNS;
Done = true;
return;
}
//OK, get the first server address
ipDNS = he.AddressList[0];
}
//Query the DNS server
//our current thread ID is used to match the reply with this process
Query myQuery = new Query(System.Threading.Thread.CurrentThread.ManagedThreadId, Query, Qtype);
//data buffer for query return value
Byte[] recBuf;
//use UDP protocol to connect
udpClient = new UdpClient();
do {
try {
//connect to given nameserver, port 53 (DNS)
udpClient.Connect(DNS, 53);
//send query
udpClient.Send(myQuery.buf, myQuery.buf.Length);
//IPEndPoint object allow us to read datagrams..
//..selecting only packet coming from our nameserver and port
IPEndPoint RemoteIpEndPoint = new IPEndPoint(ipDNS, 53);
//Blocks until a message returns on this socket from a remote host.
recBuf = udpClient.Receive(ref RemoteIpEndPoint);
udpClient.Close();
} catch (Exception e) {
//connection error, probably a wrong server address
udpClient.Close();
Error = 99;
ErrorTxt = e.Message + "(server:" + DNS + ")";
Done = true;
return;
}
//repeat until we get the reply with our threadID
} while (System.Threading.Thread.CurrentThread.ManagedThreadId != ((recBuf[0] * 256) + recBuf[1]));
//Check the DNS reply
//check if bit QR (Query response) is set
if (recBuf[2] < 128) {
//response byte not set (probably a malformed packet)
Error = 2;
ErrorTxt = "Query response bit not set";
Done = true;
return;
}
//check if RCODE field is 0
if ((recBuf[3] & 15) > 0) {
//DNS server error, invalid reply
switch (recBuf[3] & 15) {
case 1:
Error = 31;
ErrorTxt = "Format error. The nameserver was unable to interpret the query";
break;
case 2:
Error = 32;
ErrorTxt = "Server failure. The nameserver was unable to process the query.";
break;
case 3:
Error = 33;
ErrorTxt = "Name error. Check provided domain name!!";
break;
case 4:
Error = 34;
ErrorTxt = "Not implemented. The name server does not support the requested query";
break;
case 5:
Error = 35;
ErrorTxt = "Refused. The name server refuses to reply for policy reasons";
break;
default:
Error = 36;
ErrorTxt = "Unknown. The name server error code was: " + Convert.ToString((recBuf[3] & 15));
break;
}
Done = true;
return;
}
//OK, now we should have valid header fields
int QDcnt, ANcnt, NScnt, ARcnt;
int index;
QDcnt = (recBuf[4] * 256) + recBuf[5];
ANcnt = (recBuf[6] * 256) + recBuf[7];
NScnt = (recBuf[8] * 256) + recBuf[9];
ARcnt = (recBuf[10] * 256) + recBuf[11];
index = 12;
//sometimes there are no erros but blank reply... ANcnt == 0...
if (ANcnt == 0) { // if blackhole list query, means no spammer !!//if ((ANcnt == 0) & (IS_BLACKLIST_QUERY == false))
//error blank reply, return an empty array
Error = 4;
ErrorTxt = "Empty string array";
Done = true;
return;
}
//Decode received information
string s1;
// START TEST
s1 = Encoding.ASCII.GetString(recBuf, 0, recBuf.Length);
// END TEST
if (QDcnt > 0) {
//we are not really interested to this string, just parse and skip
s1 = "";
index = parseString(recBuf, index, out s1);
index += 4; //skip root domain, Qtype and QClass values... unuseful in this contest
}
if (IS_BLACKLIST_QUERY) {
// get the answers, normally one !
// int the four last bytes there is the ip address
Error = 0;
int Last_Position = recBuf.Length - 1;
result.Add(recBuf[Last_Position - 3].ToString() + "." + recBuf[Last_Position - 2].ToString() + "." + recBuf[Last_Position - 1].ToString() + "." + recBuf[Last_Position].ToString());
Done = true;
return;
}
int count = 0;
//get all answers
while (count < ANcnt) {
s1 = "";
index = parseString(recBuf, index, out s1);
//Qtype
int QType = (recBuf[index] * 256) + recBuf[index + 1];
index += 2;
s1 += "," + QType.ToString();
//QClass
int QClass = (recBuf[index] * 256) + recBuf[index + 1];
index += 2;
s1 += "," + QClass.ToString();
//TTL (Time to live)
uint TTL = (recBuf[index] * 16777216u) + (recBuf[index + 1] * 65536u) + (recBuf[index + 2] * 256u) + recBuf[index + 3];
index += 4;
s1 += "," + TTL.ToString();
int blocklen = (recBuf[index] * 256) + recBuf[index + 1];
index += 2;
if (QType == 15) {
int MXprio = (recBuf[index] * 256) + recBuf[index + 1];
index += 2;
s1 += "," + MXprio.ToString();
}
string s2;
index = parseString(recBuf, index, out s2);
s1 += "," + s2;
result.Add(s1);
count++;
}
Error = 0;
Done = true;
}
private int parseString(byte[] buf, int i, out string s)
{
int len;
s = "";
bool end = false;
while (!end) {
if (buf[i] == 192) {
//next byte is a pointer to the string, get it..
i++;
s += getString(buf, buf[i]);
i++;
end = true;
} else {
//next byte is the string length
len = buf[i];
i++;
//get the string
s += Encoding.ASCII.GetString(buf, i, len);
i += len;
//check for the null terminator
if (buf[i] != 0) {
//not null, add a point to the name
s += ".";
} else {
//null char..the string is complete, exit
end = true;
i++;
}
}
}
return i;
}
private string getString(byte[] buf, int i)
{
string s = "";
int len;
bool end = false;
while (!end) {
len = buf[i];
i++;
s += Encoding.ASCII.GetString(buf, i, len);
i += len;
if (buf[i] == 192) {
i++;
s += "." + getString(buf, buf[i]);
return s;
}
if (buf[i] != 0) {
s += ".";
} else {
end = true;
}
}
return s;
}
}
}
Here is how you use it.
/// <summary>
/// Get the MX from the domain address.
/// </summary>
public static string getMXrecord(string domain)
{
domain = domain.Substring(domain.IndexOf('#') + 1);
string LocalDNS = GetDnsAdress().ToString();
Console.WriteLine("domain: " + domain);
// resolv the authoritative domain (type=2)
C_DNSquery DnsQry = new C_DNSquery(LocalDNS, domain, 2);
Thread t1 = new Thread(new ThreadStart(DnsQry.doTheJob));
t1.Start();
int timeout = 20;
while ((timeout > 0) & (!DnsQry.Done)) {
Thread.Sleep(100);
timeout--;
}
if (timeout == 0) {
if (DnsQry.udpClient != null) {
DnsQry.udpClient.Close();
}
t1.Abort();
DnsQry.Error = 100;
}
string[] ns1;
string MyNs = "";
if (DnsQry.Error == 0) {
ns1 = DnsQry.result[0].Split(',');
MyNs = ns1[4];
t1.Abort();
} else {
t1.Abort();
MyNs = LocalDNS;
}
// Resolve MX (type = 15)
DnsQry = new C_DNSquery(MyNs, domain, 15);
Thread t2 = new Thread(new ThreadStart(DnsQry.doTheJob));
t2.Start();
timeout = 20;
string TTL = "";
string MXName = "";
Int32 preference = 9910000;
while ((timeout > 0) & (!DnsQry.Done)) {
Thread.Sleep(100);
timeout--;
}
if (timeout == 0) {
if (DnsQry.udpClient != null) {
DnsQry.udpClient.Close();
}
t2.Abort();
DnsQry.Error = 100;
}
if (DnsQry.Error == 0) {
if (DnsQry.result.Count == 1) {
string[] ns2 = DnsQry.result[0].Split(',');
MXName = ns2[5];
TTL = ns2[3];
preference = Int32.Parse(ns2[4]);
Console.WriteLine("domaine: {0} MX: {1} time: {2} pref: {3} ttl: {4}", domain.Substring(domain.IndexOf('#') + 1), MXName,
DateTime.Now, preference, TTL);
} else {
for (int indns = 0; indns <= DnsQry.result.Count - 1; indns++) {
string[] ns2 = DnsQry.result[indns].Split(',');
if (Int32.Parse(ns2[4]) < preference) {
MXName = ns2[5];
TTL = ns2[3];
preference = Int32.Parse(ns2[4]);
Console.WriteLine("domain: {0} MX: {1} time: {2} pref: {3} ttl: {4}", domain.Substring(domain.IndexOf('#') + 1), MXName,
DateTime.Now, preference, TTL);
}
}
}
}
return MXName;
}
I wrote a simply URL for that means
https://devselz.com/social/sign/buttons/dashboard/default.aspx?a=ciee&email=emailaddresstocheckifexistsornot#anydomain.com
Do not abuse
Return 1 if email exists or may exist, 0 if not
Works great in order to check:
gmail and gmail pro (domains not #gmail) accounts.
hotmail
For others like yahoo always returns 1
You can use this open source library to do almost any kind of query you would usually need.
Usage:
DnsClient dnsClient = new DnsClient();
string mxDomain = dnsClient.ResolveMX("example.com");
string mxDomainIP = dnsClient.ResolveMX("example.com", true);
string mxDomainIPv6 = dnsClient.ResolveMX("example.com", true, true);
I'm working on something that requires traversing through the file system and for any given path, I need to know how 'deep' I am in the folder structure. Here's what I'm currently using:
int folderDepth = 0;
string tmpPath = startPath;
while (Directory.GetParent(tmpPath) != null)
{
folderDepth++;
tmpPath = Directory.GetParent(tmpPath).FullName;
}
return folderDepth;
This works but I suspect there's a better/faster way? Much obliged for any feedback.
Off the top of my head:
Directory.GetFullPath().Split("\\").Length;
I'm more than late on this but I wanted to point out Paul Sonier's answer is probably the shortest but should be:
Path.GetFullPath(tmpPath).Split(Path.DirectorySeparatorChar).Length;
I'm always a fan the recursive solutions. Inefficient, but fun!
public static int FolderDepth(string path)
{
if (string.IsNullOrEmpty(path))
return 0;
DirectoryInfo parent = Directory.GetParent(path);
if (parent == null)
return 1;
return FolderDepth(parent.FullName) + 1;
}
I love the Lisp code written in C#!
Here's another recursive version that I like even better, and is probably more efficient:
public static int FolderDepth(string path)
{
if (string.IsNullOrEmpty(path))
return 0;
return FolderDepth(new DirectoryInfo(path));
}
public static int FolderDepth(DirectoryInfo directory)
{
if (directory == null)
return 0;
return FolderDepth(directory.Parent) + 1;
}
Good times, good times...
If you use the members of the Path class, you can cope with localizations of the path separation character and other path-related caveats. The following code provides the depth (including the root). It's not robust to bad strings and such, but it's a start for you.
int depth = 0;
do
{
path = Path.GetDirectoryName(path);
Console.WriteLine(path);
++depth;
} while (!string.IsNullOrEmpty(path));
Console.WriteLine("Depth = " + depth.ToString());
Assuming your path has already been vetted for being valid, in .NET 3.5 you could also use LINQ to do it in 1 line of code...
Console.WriteLine(#"C:\Folder1\Folder2\Folder3\Folder4\MyFile.txt".Where(c
=> c = #"\").Count);
If the directory has a backslash at the end, you get a different answer than when it doesn't. Here's a robust solution to the problem.
string pathString = "C:\\temp\\"
var rootFolderDepth = pathString.Split(Path.DirectorySeparatorChar).Where(i => i.Length > 0).Count();
This returns a path length of 2. If you do it without the where statement, you get a path length of 3 or a path length of 2 if you omit the last separator character.
Maybe someone need also some performance testing...
double linqCountTime = 0;
double stringSplitTime = 0;
double stringSplitRemEmptyTime = 0;
int linqCountFind = 0;
int stringSplitFind = 0;
int stringSplitRemEmptyFind = 0;
string pth = #"D:\dir 1\complicated dir 2\more complicated dir 3\much more complicated dir 4\only dir\another complicated dir\dummy\dummy.dummy.45682\";
//Heat Up
DateTime dt = DateTime.Now;
for (int i = 0; i < 10000; i++)
{
linqCountFind = pth.Count(c => c == '\\');
}
_= DateTime.Now.Subtract(dt).TotalMilliseconds;
dt = DateTime.Now;
for (int i = 0; i < 10000; i++)
{
stringSplitFind = pth.Split('\\').Length;
}
_ = DateTime.Now.Subtract(dt).TotalMilliseconds;
dt = DateTime.Now;
for (int i = 0; i < 10000; i++)
{
stringSplitRemEmptyFind = pth.Split(new char[] { '\\' }, StringSplitOptions.RemoveEmptyEntries).Length;
}
_ = DateTime.Now.Subtract(dt).TotalMilliseconds;
dt = DateTime.Now;
//Testing
dt = DateTime.Now;
for (int i = 0; i < 1000000; i++)
{
linqCountFind = pth.Count(c => c == '\\');
}
linqCountTime = DateTime.Now.Subtract(dt).TotalMilliseconds; //linq.Count: 1390 ms
dt = DateTime.Now;
for (int i = 0; i < 1000000; i++)
{
stringSplitFind = pth.Split('\\').Length-1;
}
stringSplitTime = DateTime.Now.Subtract(dt).TotalMilliseconds; //string.Split: 715 ms
dt = DateTime.Now;
for (int i = 0; i < 1000000; i++)
{
stringSplitRemEmptyFind = pth.Split(new char[] { '\\' }, StringSplitOptions.RemoveEmptyEntries).Length;
}
stringSplitRemEmptyTime = DateTime.Now.Subtract(dt).TotalMilliseconds; // string.Split with RemoveEmptyEntries option: 720 ms
string linqCount = "linqCount - Find: "+ linqCountFind + "; Time: "+ linqCountTime.ToString("F0") +" ms"+ Environment.NewLine;
string stringSplit = "stringSplit - Find: " + stringSplitFind + "; Time: " + stringSplitTime.ToString("F0") + " ms" + Environment.NewLine;
string stringSplitRemEmpty = "stringSplitRemEmpty - Find: " + stringSplitRemEmptyFind + "; Time: " + stringSplitRemEmptyTime.ToString("F0") + " ms" + Environment.NewLine;
MessageBox.Show(linqCount + stringSplit + stringSplitRemEmpty);
// Results:
// linqCount - Find: 9; Time: 1390 ms
// stringSplit - Find: 9; Time: 715 ms
// stringSplitRemEmpty - Find: 9; Time: 720 ms
So, for most cases, the best is string.split() (see results in code comments).
string.Split(new char[] { '\\' }, StringSplitOptions.RemoveEmptyEntries) is safer for path.
And for more complicated cases see:
https://cc.davelozinski.com/c-sharp/fastest-way-count-number-times-character-occurs-string
and
https://cc.davelozinski.com/c-sharp/c-net-fastest-way-count-substring-occurrences-string