C# How can I split this string into an array?

Question

My string is as follows:

smtp:[email protected];SMTP:[email protected];X400:C=US;A= ;P=Test;O=Exchange;S=Jack;G=Black;

I need back:

smtp:[email protected]
SMTP:[email protected]
X400:C=US;A= ;P=Test;O=Exchange;S=Jack;G=Black;

The problem is the semi-colons seperate the addresses and also part of the X400 address. Can anyone suggest how best to split this?

PS I should mentioned the order differs so it could be:

X400:C=US;A= ;P=Test;O=Exchange;S=Jack;G=Black;;smtp:[email protected];SMTP:[email protected]

There can be more than 3 address, 4, 5.. 10 etc including an X500 address, however they do all start with either smtp: SMTP: X400 or X500.

Answer 1

EDIT: With the updated information, this answer certainly won't do the trick - but it's still potentially useful, so I'll leave it here.

Will you always have three parts, and you just want to split on the first two semi-colons?

If so, just use the overload of Split which lets you specify the number of substrings to return:

string[] bits = text.Split(new char[]{';'}, 3);

Answer 2

http://msdn.microsoft.com/en-us/library/c1bs0eda.aspx check there, you can specify the number of splits you want. so in your case you would do

string.split(new char[]{';'}, 3);

Answer 3

Do the semicolon (;) split and then loop over the result, re-combining each element where there is no colon (:) with the previous element.

string input = "X400:C=US;A= ;P=Test;O=Exchange;S=Jack;G="
  +"Black;;smtp:[email protected];SMTP:[email protected]";

string[] rawSplit = input.Split(';');

List<string> result = new List<string>();
  //now the fun begins
string buffer = string.Empty;
foreach (string s in rawSplit)
{
  if (buffer == string.Empty)
  {
    buffer = s;
  }
  else if (s.Contains(':'))
  {   
    result.Add(buffer);
    buffer = s;
  }
  else
  {
    buffer += ";" + s;
  }
}
result.Add(buffer);

foreach (string s in result)
  Console.WriteLine(s);

Answer 4

This caught my curiosity .... So this code actually does the job, but again, wants tidying :)

My final attempt - stop changing what you need ;=)

static void Main(string[] args)
{
    string fneh = "X400:C=US400;A= ;P=Test;O=Exchange;S=Jack;G=Black;x400:C=US400l;A= l;P=Testl;O=Exchangel;S=Jackl;G=Blackl;smtp:[email protected];X500:C=US500;A= ;P=Test;O=Exchange;S=Jack;G=Black;SMTP:[email protected];";

    string[] parts = fneh.Split(new char[] { ';' });

    List<string> addresses = new List<string>();
    StringBuilder address = new StringBuilder();
    foreach (string part in parts)
    {
        if (part.Contains(":"))
        {
            if (address.Length > 0)
            {
                addresses.Add(semiColonCorrection(address.ToString()));
            }
            address = new StringBuilder();
            address.Append(part);
        }
        else
        {
            address.AppendFormat(";{0}", part);
        }
    }
    addresses.Add(semiColonCorrection(address.ToString()));

    foreach (string emailAddress in addresses)
    {
        Console.WriteLine(emailAddress);
    }
    Console.ReadKey();
}
private static string semiColonCorrection(string address)
{
    if ((address.StartsWith("x", StringComparison.InvariantCultureIgnoreCase)) && (!address.EndsWith(";")))
    {
        return string.Format("{0};", address);
    }
    else
    {
        return address;
    }
}

Answer 5

Try these regexes. You can extract what you're looking for using named groups.

X400:(?<X400>.*?)(?:smtp|SMTP|$)
smtp:(?<smtp>.*?)(?:;+|$)
SMTP:(?<SMTP>.*?)(?:;+|$)

Make sure when constructing them you specify case insensitive. They seem to work with the samples you gave

Answer 6

Not the fastest if you are doing this a lot but it will work for all cases I believe.

        string input1 = "smtp:[email protected];SMTP:[email protected];X400:C=US;A= ;P=Test;O=Exchange;S=Jack;G=Black;";
        string input2 = "X400:C=US;A= ;P=Test;O=Exchange;S=Jack;G=Black;;smtp:[email protected];SMTP:[email protected]";
        Regex splitEmailRegex = new Regex(@"(?<key>\w+?):(?<value>.*?)(\w+:|$)");

        List<string> sets = new List<string>();

        while (input2.Length > 0)
        {
            Match m1 = splitEmailRegex.Matches(input2)[0];
            string s1 = m1.Groups["key"].Value + ":" + m1.Groups["value"].Value;
            sets.Add(s1);
            input2 = input2.Substring(s1.Length);
        }

        foreach (var set in sets)
        {
            Console.WriteLine(set);
        }

        Console.ReadLine();

Of course many will claim Regex: Now you have two problems. There may even be a better regex answer than this.

Answer 7

You could always split on the colon and have a little logic to grab the key and value.

string[] bits = text.Split(':');
List<string> values = new List<string>();
for (int i = 1; i < bits.Length; i++)
{
 string value = bits[i].Contains(';') ? bits[i].Substring(0, bits[i].LastIndexOf(';') + 1) : bits[i];
 string key = bits[i - 1].Contains(';') ? bits[i - 1].Substring(bits[i - 1].LastIndexOf(';') + 1) : bits[i - 1];
 values.Add(String.Concat(key, ":", value));
}

Tested it with both of your samples and it works fine.

Answer 8

May I suggest building a regular expression

(smtp|SMTP|X400|X500):((?!smtp:|SMTP:|X400:|X500:).)*;?

or protocol-less

.*?:((?![^:;]*:).)*;?

in other words find anything that starts with one of your protocols. Match the colon. Then continue matching characters as long as you're not matching one of your protocols. Finish with a semicolon (optionally).

You can then parse through the list of matches splitting on ':' and you'll have your protocols. Additionally if you want to add protocols, just add them to the list.

Likely however you're going to want to specify the whole thing as case-insensitive and only list the protocols in their uppercase or lowercase versions.

The protocol-less version doesn't care what the names of the protocols are. It just finds them all the same, by matching everything up to, but excluding a string followed by a colon or a semi-colon.

Answer 9

Split by the following regex pattern

string[] items = System.Text.RegularExpressions.Split(text, ";(?=\w+:)");

EDIT: better one can accept more special chars in the protocol name.

string[] items = System.Text.RegularExpressions.Split(text, ";(?=[^;:]+:)");

Answer 10

here is another possible solution.

string[] bits = text.Replace(";smtp", "|smtp").Replace(";SMTP", "|SMTP").Replace(";X400", "|X400").Split(new char[] { '|' });

bits[0], bits[1], and bits[2] will then contains the three parts in the order from your original string.

Answer 11

Lots of attempts. Here is mine ;)

string src = "smtp:[email protected];SMTP:[email protected];X400:C=US;A= ;P=Test;O=Exchange;S=Jack;G=Black;";

Regex r = new Regex(@"
   (?:^|;)smtp:(?<smtp>([^;]*(?=;|$)))|
   (?:^|;)x400:(?<X400>.*?)(?=;x400|;x500|;smtp|$)|
   (?:^|;)x500:(?<X500>.*?)(?=;x400|;x500|;smtp|$)",
RegexOptions.IgnoreCase | RegexOptions.IgnorePatternWhitespace);

foreach (Match m in r.Matches(src))
{
 if (m.Groups["smtp"].Captures.Count != 0)
  Console.WriteLine("smtp: {0}", m.Groups["smtp"]);
 else if (m.Groups["X400"].Captures.Count != 0)
  Console.WriteLine("X400: {0}", m.Groups["X400"]);
 else if (m.Groups["X500"].Captures.Count != 0)
  Console.WriteLine("X500: {0}", m.Groups["X500"]); 
}

This finds all smtp, x400 or x500 addresses in the string in any order of appearance. It also identifies the type of address ready for further processing. The appearance of the text smtp, x400 or x500 in the addresses themselves will not upset the pattern.

Answer 12

You can use the following regular expression, compiled IgnoreCase and RightToLeft to grab each individual part:

((?<protocol>x[45]00|smtp):(?<payload>([^:;]+);?)+)

The RightToLeft is required to keep a trailing 'smtp' or 'x400' from getting added onto a match. Works testing with Ultrapico Expresso 3.0 and all of your test inputs.

Answer 13

This works!

    string input =
        "smtp:[email protected];SMTP:[email protected];X400:C=US;A= ;P=Test;O=Exchange;S=Jack;G=Black;";
    string[] parts = input.Split(';');
    List<string> output = new List<string>();
    foreach(string part in parts)
    {
        if (part.Contains(":"))
        {
            output.Add(part + ";");
        }
        else if (part.Length > 0)
        {
            output[output.Count - 1] += part + ";";
        }
    }
    foreach(string s in output)
    {
        Console.WriteLine(s);
    }