c# combobox values bound from database, and adding initial values

Use InsertAt method of the combobox after it is bound to add values

Guid.Empty is the usual representation for None.  It represents this value:

"00000000-0000-0000-0000-000000000000"

Bob

See this

http://www.thescripts.com/forum/thread165843.html

basically you do

ComboBox1.Items.InsertAt(0, "All")

pComboName.DataSource = oDataHelper.moDataSet.Tables[0];
            pComboName.DataTextField = pDataTextField;
            pComboName.DataValueField = pDataValueField;
            pComboName.DataBind();
     
                ListItem listItem = new ListItem();
                listItem.Text = "All";
                listItem.Value = "0";
                pComboName.Items.Insert(0, listItem);

this is a windows applicaiton, isn't listbox only a web collection?  What namespace do I have to use?

ListItem is an ASP.NET class.  You need System.Windows.Forms.ListBox.

Bob

That does not work I am getthign this error
"Items collection cannot be modified when the DataSource property is set."



                cmbTestPlanCode.DataSource = m_ds.TestPlanCodes;
                cmbTestPlanCode.DisplayMember = m_ds.TestPlanCodes.TestPlanCodeColumn.ColumnName;
                cmbTestPlanCode.ValueMember = m_ds.TestPlanCodes.TestPlanCodeColumn.ColumnName;

                ListBox lb = new ListBox();
                lb.Text = "ALL";
                lb.ValueMember = "0";
                cmbTestPlanCode.Items.Insert(0, lb);

Add the items to the data source, and refresh the ComboBox.

Bob

I don't see how that will help.  First of all, I want to add 2 values, so I would have to add two rows, with a guid of the "00000000-0000-0000-0000-000000000000", which will not work since it is the primary key.  I suppose I could use another guid, then check for it later, but that seems like a hack.  Even if that did work though, the sorting would be out of wack.

Has anyone actually done this?  These answers seem to be guesses.   I appreciate the help, but this is a pretty big waste of time.  I was hoping someone who has done this will propose an answer.  None of the answers even came remotely close to working.