Using New ComboBox ActiveX With C#

Introduction

When I create a project for using a DataGrid with a ComboBox, I hope to get a resizable ComboBox to set its height as the height of the DataGrid cell. This is my attempt to create a resizable ComboBox ActiveX, now I can change its Height. Some programmers use a Form, ListBox, TextBox and a Button to create a ComboBox, but I am using a Panel, ComboBox, TextBox and a Button to create my ActiveX. Using a Panel to hide the upper part of the ComboBox and using this Panel as the container for the TextBox and Button.



About the Project of my ActiveX:

• Name of the Project is: MKCombo
• Name of UserControl is: KCombo
• Name of Panel is: ComboHide
• Name of ComboBox is: ComboCtrl
• Name of TextBox is: ComboText
• Name of Button is: ComboButton

After you expand the files: ComboC.zip, you can open "SizableCombo" solution to read the code of my ActiveX in the "MKCombo" project and read the code to test the ActiveX in the "SizableCombo" project.

I try to use "DataSource" to bind my ActiveX with data but I can't, so then I use another idea.

My ActiveX has:

• Event: cmbSelectedChanged for SelectedIndexChanged event.
• Property: cmbBorderStyle for BorderStyle property.
• Property: cmbSelectedIndex for SelectedIndex property.
• Property: cmbSelectedItem for SelectedItem property.
• Property: cmbText for Text property.
• Property: cmbItemsCount for Items.Count property.
• Method: cmbAddItem for Items.Add method.
• Method: cmbClear for Items.Clear method.

About the Code

Code to bind the ActiveX with data:

public void cmbBindData(string cmbSql, OleDbConnection cmbCnn, string cmbField)
{
    if (cmbCnn.State == ConnectionState.Open)
        cmbCnn.Close();
    cmbCnn.Open();
    OleDbCommand cmdReader = new OleDbCommand(cmbSql, cmbCnn);
    OleDbDataReader datRdr = cmdReader.ExecuteReader();
    ComboCtrl.Items.Clear();
    while (datRdr.Read())
    {
        ComboCtrl.Items.Add(datRdr[cmbField]);
    }
    ComboCtrl.SelectedIndex = 0;
}

Remark

When the test project is executed, please resize any row to see how the ComboBox changes its height.

I hope this article is useful. If you have any idea, please tell me.