Binding a HashTable to a ComboBox [C#]

December 30th, 2008  | Tags:

On other day i was trying to use HashTable to display records in a combo box being the Key the Display Member and Value the ValueMember like so:

HashTable hash = new HashTable();
ComboBox ddlText = new ComboBox();
 
hash.Add("FirstKey", 1000);
hash.Add("SecondKey", 1005);            
 
ddlText.BeginUpdate();
 
ddlText.ValueMember = "Value";
ddlText.DisplayMember = "Key";
ddlText.DataSource = hash;
 
ddlText.EndUpdate();

But in order to bind an object to a ComboBox it has to implement IList or IListSource interface.

So i created a new class derived from HashTable implementing the IListSource interface:

public class EnhancedHashTable : Hashtable, IListSource
{
    public bool ContainsListCollection
    {
        get { return true; }
    }
 
    public IList GetList()
    {
        List list = new List();
        foreach (DictionaryEntry obj in this)
            list.Add(obj);
 
        return list;
    }
}

Using a Dictionary…

public class EnhancedDictionary:Dictionary, IListSource
{
    public bool ContainsListCollection
    {
      get { return true; }
    }
 
    public IList GetList()
    {
        List > list = new List>();
        foreach (KeyValuePair entry in this)
             list.Add(entry);
 
        return list;
    }
}

UPDATE: Looks like there is a simpler solution, instead of implementing this class. You simply use .NET 2.0 BindingSource class.

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First post..

October 1st, 2008  | Tags:

Here i am writing my first blog post.

The main reasons for creation of this blog are:

  • A chance to practice my english writing (which is very rusty).
  • Share knowlegde on the various IT tecnologies and programming Languages that i’ve gathered through out the years.
  • To share some personal thoughts and curious subjects.

Well, enough said.  On with the posts.. :).

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