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WinForms ComboBox

I'm trying to mark one of the combobox items as selected.
So I am building my combobox like this:
var drop = new Dictionary<int, string>();
while (RegReader.Read())
{
drop.Add(Convert.ToInt32(RegReader["intRulesID"]), RegReader["txtName"].ToString());
}
RegRuleDrop.DataSource = new BindingSource(drop, null);
RegRuleDrop.DisplayMember = "Value";
RegRuleDrop.ValueMember = "Key";
Now, one of the items within the RegRuleDrop should be pre selected based on a value from a reader above this code.
Now, the problem is that I need to select value based on the actual ListItem VALUE and not TEXT.
So as an example
drop.Add(1, "Test");
drop.Add(2, "Test2");
drop.Add(3, "Test3");
I need to find the index using 1,2 or 3 not Test, Test2 or Test3
Any ideas?

When you have the DataSource set to a BindingSource the only action needed to select an item given a value belonging to the ValueMember property is
drop.Add(1, "Test1");
drop.Add(2, "Test2");
drop.Add(99, "Test99");
drop.Add(3, "Test3");
.....
RegRuleDrop.SelectedValue = 99

ValueMember from ComboBox.Items[i] using WinForms c#

I fill out a ComboBox using below code:
cbxLines.DisplayMember = "Value";
cbxLines.ValueMember = "Key";
cbxLines.DataSource = new BindingSource(GetProductionLines(), null);
private Dictionary<int, string> GetProductionLines()
Now I want to fill out a ListView with every DisplayMember from the ComboBox among other info:
lvSelectedSetup.Items.Clear();
for (int i = 0; i <= cbxLines.Items.Count - 1; i++)
{
ListViewItem item = new ListViewItem();
item.SubItems.Add(cbxLines.Items[i].ToString()); <-- How to Get DisplayMember
item.SubItems.Add(cbxFromDate.Text);
item.SubItems.Add(cbxToDate.Text);
lvSelectedSetup.Items.Add(item);
}
But I don't know how to get either the ValueMember or DisplayMember from the ComboBox.
I was trying doing the following, but get stuck:
item.SubItems.Add(cbxLines.Items[i].GetType().GetProperty(cbxLines.ValueMember).GetValue(cbxLines,null))
Any Advice?

Gets the key in the key/value pair.
((KeyValuePair<int, string>)cbxLines.Items[i]).Key
Gets the value in the key/value pair.
((KeyValuePair<int, string>)cbxLines.Items[i]).Value

Parsing SelectedValue of a ListBox to int using C#.NET

I've a listbox that uses a dictionary as a datasource.
When I want to parse the listbox's selectedvalue to a int variable, it gives me a cast exception.
The dictionary~
Dictionary<int, string> AssetDictionary = new Dictionary<int, string>();
The listbox (lstAsset) datasource~
lstAsset.DisplayMember = "Value";
//lstAssetType.ValueMember = "Key"; //This should be lstAsset as corrected in the next line
lstAsset.ValueMember = "Key";
lstAsset.DataSource = new BindingSource(AssetDictionary, null);
The line where exception occurs~
int ush = (int)lstAsset.SelectedValue; //Specified cast is not valid.
Where am I doing wrong?

Provide Value Member to correct control.
lstAsset.ValueMember = "Key";
and use
int ush = Convert.ToInt32(lstAsset.SelectedValue.ToString());

ComboBox AutoComplete with Key/Value Pair

I have a ComboBox with the following code:
private void comboBox1_TextChanged(object sender, EventArgs e)
{
using (var service = WebServiceHelper.GetCoreService())
{
string physicianXml = service.SearchPhysicians(SessionInfo.Current.ClientCode, SessionInfo.Current.MachineName,
SessionInfo.Current.Username, comboBox1.Text);
var physicians = PhysicianItemList.FromXml(physicianXml);
AutoCompleteStringCollection autoCompleteStringCollection = new AutoCompleteStringCollection();
foreach (var physician in physicians.Items)
{
autoCompleteStringCollection.Add(physician.LastName + ", " + physician.FirstName);
}
comboBox1.AutoCompleteCustomSource = autoCompleteStringCollection;
comboBox1.Select(comboBox1.Text.Length, 0);
}
}
Basically, a user types the first few characters of a physician's name and it should populate the auto-complete list with the top 100 matching records. It works great, but I need to associate it back to a key (either the PK from the table, or the Physician's NPI number). It seems the AutoCompleteStringCollection doesn't support keys. Can anyone suggest a way of doing this? There are approximately 7 million records in the table, so I don't want to prepopulate the ComboBox.
Thanks

When you build your AutoCompleteStringCollection, build a Dictionary<String, int> for the name, id pairs as well. Then use some event (textbox validation or user submit/save click) to lookup and set the id. You could store the dictionary on the textbox Tag.
Edit
For some reason I thought you were working with a textbox control. Forget about the AutoCompleteStringCollection and just build a Dictionary<String, int>. For the combobox set your autocompletesource to ListItems, set the combobox display name and value and set the datasource to the dictionary.
combobox.DisplayMember = "key";
combobox.ValueMember = "value";
combobox.AutocompleteSource = AutocompleteSource.ListItems;
combobox.DataSource = myDictionary;
However you should only populate the datasource and autocomplete once when the user enters n characters in the combobox, otherwise it gets buggy. I tried to use this for a dynamic autocomplete once (eg the list clears if the user clear the text and retypes), but I had to forget about the combobox and use a hybrid textbox listbox approach much like this user

It looks like your problem is that AutoCompleteStringComplete was made specifically for strings (hence, the name).
You may want to look into the parents (IList, ICollection, IEnumerable) and see if you can homebrew something templated toward a key/value struct.

Too late but maybe someone will use this code :
this.AutoCompleteSource = System.Windows.Forms.AutoCompleteSource.ListItems;
this.AutoCompleteMode = System.Windows.Forms.AutoCompleteMode.SuggestAppend;
RNProveedor rnProveedor = new RNProveedor();
var listaProveedores = rnProveedor.Buscar();
Dictionary<int, String> dicTemp = new Dictionary<int, string>();
foreach (var entidad in listaProveedores)
{
dicTemp.Add(entidad.ProvNro, entidad.ProNombre);
}
this.DataSource = new BindingSource(dicTemp, null);
this.DisplayMember = "Value";
this.ValueMember = "Key";
And to select the value
public int GetValorDecimal()
{
KeyValuePair<int, string> objeto = (KeyValuePair<int, string>)this.SelectedItem;
return objeto.Key;
}
With this example you won't have any problem with duplicated strings as the examples above

Binding empty dictionary to a listbox

When i try to bind a dictionary to a listbox I get an ArgumentException. Cannot bind to the new value member.
I use the following code.
Can any one tell me what is wrong. Because when i enter i row in the dictionary its working fine...
this.contactpersonenListBox = new Dictionary<int, string>();
lsContactpersonen.DataSource = new BindingSource(this.contactpersonenListBox, null);
lsContactpersonen.DisplayMember = "Value";
lsContactpersonen.ValueMember = "Key";

It doesn't make a ton of sense to bind an empty dictionary since the dictionary object doesn't report any changes, so adding an item to the dictionary after setting the data source won't show up in the ListBox.
But to get rid of the error, try setting it like this:
BindingSource b = new BindingSource();
b.DataSource = this.contactpersonenListBox;
lsContactpersonen.DisplayMember = "Value";
lsContactpersonen.ValueMember = "Key";
lsContactpersonen.DataSource = b;