Hello Scott Steinman,
Thank you for writing. Since your requirement is not to have multiple collections you can consider using two
DataView objects. In the DataView you can set a filter expression on the combo box that displays a subset of items. Here is how you can do this:
public partial class Form1 : Form
{
DataTable mainTable = null;
DataView subView = null;
public Form1()
{
InitializeComponent();
mainTable = this.CreateTable();
subView = new DataView(mainTable);
string displayMember = "Name";
string valueMember = "Value";
this.radComboBox1.DisplayMember = displayMember;
this.radComboBox1.ValueMember = valueMember;
this.radComboBox1.DataSource = mainTable.DefaultView;
this.radComboBox2.DisplayMember = displayMember;
this.radComboBox2.ValueMember = valueMember;
this.radComboBox2.DataSource = subView;
}
private DataTable CreateTable()
{
DataTable result = new DataTable();
result.Columns.Add(new DataColumn("Name", typeof(string)));
result.Columns.Add(new DataColumn("Value", typeof(int)));
for (int i = 0; i < 70; ++i)
{
DataRow row = result.NewRow();
row["Name"] = i.ToString();
row["Value"] = i;
result.Rows.Add(row);
}
return result;
}
private void radComboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
int value = (int)this.radComboBox1.SelectedValue;
// Compose filter expression based on the selected value in the first combo box.
// This is a rather silly filter but it serves the example. You can provide whaterver filter you need
// provided it has the correct syntax. Look up the RowFilter property of DataView in the MSDN for details
// on the syntax.
string filter = "Value = " + value.ToString();
this.subView.RowFilter = filter;
}
}
Please write again if you need further assistance.
Sincerely yours,
Victor
the Telerik team