c# - Removing duplicate entries from arralist -

i have arraylist "templist" after point of time saw lot of duplicate values added arraylist, thought of remove duplicates.when googled found solutions of them confusing.some telling sort arralist , find , remove duplicates telling use distinct, somewhere telling use hashlist. way dont want replace arraylist other structures. can provide me logic prevent duplicates arraylist?

the code having

 public class templist : arraylist  {    //some logic behind arraylist  }                     templist items = new templist();                         if (!(obj testobject) && !(obj leafobject))                        {                           items.add(obj);                        }                       if (items.count > 0)                     {                        ssendobjectcollection(items);                     }                  static public void sendobjectcollection(templist col)                 {                   try                    {                        col.sort();                   }                     catch(system.exception exception)                     {                     }                  } 

update

i did code

public static string[] removeduplicates(string[] s)  {      hashset<string> set = new hashset<string>(s);      string[] result = new string[set.count];      set.copyto(result);      return result;  } 

then called in exisitng function sendobjectcollection() removeduplicates(col); throwing errors, can body guide me going wrong here?

there 2 problems have solve. firstly have remove duplicate values using:

myarray = new arraylist(myarray.distinct().toarray()); 

and checking duplicate before add value array list:

if(myarray.indexof("value") == -1) {myarray.add("value");} 

hope help