Using OOP in WinForms Correctly - oop

Question

I have 3 WinForm controls, each of which have the same functionality...
a) load data to a datagridview
b) approve data
c) run report
I want to build this with OOP in mind. I am beginning to learn OOP and to implement it into my applications.
1) Create Abstract control class that contains below abstract methods...
- LoadData()
- ApproveData()
- RunReport()
and properties...
- UserID
- PeriodRunDate
2) Create a control subclass for each of the 3 controls and implement the abstract class
3) add custom code for each of these methods
4) load these subclass controls in a Client WinForm, and call methods from client form.
Below is my code to date. Am I on the correct path? How do I use the abstract properties in the client form and subclasses?
// Abstract Class Control code...
public partial class AbstractUserControl : UserControl
{
protected abstract string userID { get; }
protected abstract string periodRunDate { get; }
protected abstract void LoadData(DoWorkEventArgs doWorkEventArgs);
protected abstract void DataLoaded(RunWorkerCompletedEventArgs runWorkerCompletedEventArgs);
protected abstract void ApproveData();
protected abstract void RunReport();
public void LoadDataButton_Click(object sender, System.EventArgs eventArgs)
{
this._uiLoadDataBackgroundWorker.RunWorkerAsync();
}
private void _uiLoadDataBackgroundWorker_DoWork(object sender, DoWorkEventArgs doWorkEventArgs)
{
this.LoadData(doWorkEventArgs);
}
private void _uiLoadDataBackgroundWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs runWorkerCompletedEventArgs)
{
this.DataLoaded(runWorkerCompletedEventArgs);
}
}
// first subclass usercontrol
public partial class DetailsUserControl : UserControl
{
private DataSet.DataTable DataTable;
protected override void LoadData(DoWorkEventArgs doWorkEventArgs)
{
DataSetTableAdapters.DataTableAdapter
dataTableAdapter = new DataSetTableAdapters.DataTableAdapter();
this.DataTable = new DataSet.DataTable();
DataTableAdapter.FillData(this.DataTable, userID, periodRunDate);
}
protected override void DataLoaded(RunWorkerCompletedEventArgs runWorkerCompletedEventArgs)
{
this.bindingSource.DataSource = this.DataTable;
}
protected override void ApproveData()
{
// check each row ticked in the datagridview
// and update record in database
}
}
// Client WinForm that loads UserControl(s); Uses RunButton click event
// to call LoadButton Click in subclass controls...
private AbstractUserControl abstractUserControl;
private void RunButton_Click(object sender, EventArgs e)
{
// bind to load data button click event in abstract class
this.LoadDataButton.Click += this.abstractUserControl.LoadDataButton_Click;
}

Answer 1

Although the approach of having a base class that is inherited is a perfectly good one, it unfortunately does not play well with the Windows Forms designer. So if your intention is to double click the class file and then use the Form designer to drag and drop etc. then it will not work. Instead I would recommend the following alternative pattern.
Create a standard UserControl and then you can design it using the Form designer as per usual. This one control will be used for all three related scenarios you have. Then create a base class with three derived classes that implement the business logic you need.
Add a property or method to the UserControl that allows you to inject the business logic instance into the control. The control then calls the exposed abstract methods/properties of the instance. So you have a single user interface control that has a business logic instance injected to determine the essence of the processing performed.