Checking for duplicate strings in an array

Question

1.00/5 (1 vote)

See more:

Hi I am using this method to remove empty entries, now I need to check for duplicates but I am on a very old version of VS 2005 theres no linq I can't use the duplicate method. Any help would be nice. Thank!

String[] hostName = htbclb.Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries);

Posted 21-Oct-12 18:26pm

Member 9473758

Add a Solution

Comments

Sergey Alexandrovich Kryukov 22-Oct-12 0:44am

First of all, this is not a question. What have you done so far? It's completely unclear how split is related to the question. First of all you need to think about is why do you have duplicate in first place. Maybe, you should have written the code not allowing to create duplicates; it would be easier and way more efficient.
--SA

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Arshvinder Sehmi · Accepted Answer · 2012-10-21T19:39:00

You can tweak the solution to make to suit your needs!

One possible solution is using the following snippet.

C#

public static class ListExtensions
   {
       /// <summary>
       /// Add
       /// </summary>
       /// <typeparam name="T"></typeparam>
       /// <param name="List"></param>
       /// <param name="item"></param>
       /// <returns></returns>
       public static bool Add<T>(this List<T> List, T item)
       {
           bool isAdded = false;

           // if this is not a duplicate item
           if (!List.Contains(item))
           {
               // Add this item in the list
               List.Add(item);
               isAdded = true;
           }
           return isAdded;
       }

       /// <summary>
       /// ToStringEx
       /// </summary>
       /// <param name="StringArray"></param>
       /// <returns></returns>
       public static string ToStringEx(this string[] StringArray)
       {
           StringBuilder stringBuilder = new StringBuilder();
           foreach (string stringItem in StringArray)
           {
               stringBuilder.AppendFormat("{0},", stringItem);
           }
           return stringBuilder != null ? stringBuilder.ToString().TrimEnd (new char[] {','}) : string.Empty;
       }
   }

   public class Program
   {
       static void Main()
       {
           List<string> stringList = null;
           string longString = null;
           string[] stringArray = null;
           try
           {
               stringList = new List<string>();
               longString = "BOOK,COOK,BOOK,COOK,BOOK,LOOK,COOK,COOK,BOOK";
               stringArray = longString.Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries);

               // Enumerate over the stringArray
               foreach (string stringItem in stringArray)
               {
                   // Add this item in the list
                   stringList.Add<string>(stringItem);
               }

               // Converting List<string> to string[]
               stringArray = stringList.ToArray();

               // Converting string[] to comma delimited string
               longString = stringArray.ToStringEx();
           }
           catch (Exception ex)
           {
               Console.WriteLine(ex.StackTrace);
           }
           Console.ReadKey();
       }

Or you can stip the code from the extension methods and use inline -

C#

static void Main()
       {
           List<string> stringList = null;
           string longString = null;
           string[] stringArray = null;
           StringBuilder stringBuilder = null;
           try
           {
               stringList = new List<string>();
               longString = "BOOK,COOK,BOOK,COOK,BOOK,LOOK,COOK,COOK,BOOK";
               stringArray = longString.Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries);
               // Enumarate over the stringArray
               foreach (string stringItem in stringArray)
               {
                   // if this is not a duplicate item
                   if (!stringList.Contains(stringItem))
                   {
                       // Add this item in the list
                       stringList.Add(stringItem);
                   }
               }
               // Converting List<string> to string[]
               stringArray = stringList.ToArray();
               // Converting string[] to comma delimited string
               stringBuilder = new StringBuilder();
               foreach (string stringItem in stringArray)
               {
                   stringBuilder.AppendFormat("{0},", stringItem);
               }
               longString = stringBuilder.ToString();
           }
           catch (Exception ex)
           {
               Console.WriteLine(ex.StackTrace);
           }
           Console.ReadKey();
       }

Regards,
ErSehmi