Question

I’ve done some extensive searching before finally deciding to ask this question. I’ve followed the MSDN tutorials on creating User Controls that use Simple, Complex and Lookup Data Binding.

• Walkthrough: Creating a User Control that Supports Simple Data Binding
• Walkthrough: Creating a User Control that Supports Complex Data Binding
• Walkthrough: Creating a User Control that Supports Lookup Data Binding

And they work great…for a User Control that only uses a single Combobox or Gridview.

Now I want to create a User Control with three different Comboboxes. I want to bind each one to a different Table. The tables are ‘Names’, ‘Types’, and ‘Products’.

The MSDN tutorials involve creating DataBindingProperties for a single Combobox, but do not show how to do the same for a user control that contains more than one.

using System.Windows.Forms;
namespace CS
{
    [System.ComponentModel.LookupBindingProperties(
       "DataSource", "DisplayMember", "ValueMember", "LookupMember")]
    public partial class LookupBox : UserControl
    {
        public object DataSource
        {
            get{ return comboBox1.DataSource; }
            set{ comboBox1.DataSource = value; }
        }

        public string DisplayMember
        {
            get{ return comboBox1.DisplayMember; }
            set{ comboBox1.DisplayMember = value; }
        }

        public string ValueMember
        {
            get{ return comboBox1.ValueMember; }
            set{ comboBox1.ValueMember = value; }
        }

        public string LookupMember
        {
            get{ return comboBox1.SelectedValue.ToString(); }
            set{ comboBox1.SelectedValue = value; }
        }

        public LookupBox()
        {
            InitializeComponent();
        }
    }
}

Now, as you can see, there is only one Combobox mentioned in the code. I need to have three Comboboxes, each bound to a different table as mentioned above.

Please, I’m banging my head against the wall. I’m not too well versed in User Controls (although I have used them in ASP.NET), but it seems like a good idea make one since I’m going to be using these three Comboboxes together quite a lot in different places in my application.

Answer 1

I would create a UserControl that contained three of your LookupBox‘s. For example:

public partial class MyLookupBoxes : UserControl
{
    public LookupBox()
    {
        // Add the 3 LookupBox to this UserControl using the designer
        InitializeComponent();
        SetupDataSources();
    }

    private void SetupDataSources()
    {
        namesLookupBox1.DataSource = names_data_source_1;
        // ...
        typesLookupBox2.DataSource = types_data_srouce_2;
        // ...
        productsLookupBox3.DataSource = products_data_srouce_2;
        // ...
    }
}