Working With Business Classes

Note: additional information on the subject contained here can be obtained from an instructional video clip  at the form.suite4.net web site.

You can bind business objects of your application to a form in a form.suite4.net project. When the code for the form is generated, form.suite4.net includes code statements based on your preferred data binding method (see below).

Note: form.suite4.net concerns itself only with the presentation layer of .NET applications. Therefore, even though the code generation engine takes care of setting control property values to business object property values, you are still responsible for retrieving an instance of the business class from lower application layers and storing it back to the data store once editing of the data is complete.

s supports two different approaches to binding a business object to a form. They differ in the generated code and are based on the two most common scenarious found in working with data in a .NET environment:

1. Manual assignment of business object property values to controls and writing their values back to the business object. This is a flexible but usually rather involved approach as it entails typing lots of repetitive code statements (along the lines of myControl.Text = myBusinessObject.MyProperty) that assign business object properties to control property values. form.suite4.net's code generation engine comes in very handy here, as the "typing" is delegated to the tool — permitting the developer to concentrate on more important tasks.
2. Use of built-in Windows Forms data binding features using myControl.DataBindings.Add(…) and related operations. Microsoft's recommended approach. Easy to use for simple data manipulation operations.

This sample excerpt shows the code generation engine's output for binding a business object to form control properties using the first (manual) approach:

public void InitializeDataSource(assetm.Northwind.EmployeesRow employeesRowdata)
{
	this.SuspendLayout();
	this.Save();
	this._IsInitializing = true;
	this.Reset();
	this._EmployeesRowdata = employeesRowdata;
	if((this._EmployeesRowdata != null))
	{
		this.txtEmployeeID.Text = this._EmployeesRowdata.EmployeeID.ToString();
		this.txtTitleOfCourtesy.Text = this._EmployeesRowdata.TitleOfCourtesy;
		this.txtTitle.Text = this._EmployeesRowdata.Title;
		this.txtCountry.Text = this._EmployeesRowdata.Country;
		this.txtRegion.Text = this._EmployeesRowdata.Region;
		this.txtPostalCode.Text = this._EmployeesRowdata.PostalCode;
		this.txtCity.Text = this._EmployeesRowdata.City;
		this.txtStreet.Text = this._EmployeesRowdata.Address;
		this.txtFirstName.Text = this._EmployeesRowdata.FirstName;
		this.txtLastName.Text = this._EmployeesRowdata.LastName;
	} // end if((this._EmployeesRowdata != null))
	this.ResumeLayout(false);
	this._IsInitializing = false;
	this._IsDirty = false;
} // end public void InitializeDataSource(assetm.Northwind.EmployeesRow employeesRowdata)

This is the output for the same form when using Windows Forms databinding:

public void InitializeDataSource(assetm.Northwind.EmployeesRow employeesRowdata)
{
	this.SuspendLayout();
	// Clear DataBindings for all components.
	this.txtTitleOfCourtesy.DataBindings.Clear();
	this.txtTitle.DataBindings.Clear();
	this.txtCountry.DataBindings.Clear();
	this.txtRegion.DataBindings.Clear();
	this.txtPostalCode.DataBindings.Clear();
	this.txtCity.DataBindings.Clear();
	this.txtStreet.DataBindings.Clear();
	this.txtFirstName.DataBindings.Clear();
	this.txtLastName.DataBindings.Clear();
	this._EmployeesRowdata = employeesRowdata;
	if((this._EmployeesRowdata != null))
	{
		this.txtTitleOfCourtesy.DataBindings.Add("Text", this._EmployeesRowdata, "TitleOfCourtesy");
		this.txtTitle.DataBindings.Add("Text", this._EmployeesRowdata, "Title");
		this.txtCountry.DataBindings.Add("Text", this._EmployeesRowdata, "Country");
		this.txtRegion.DataBindings.Add("Text", this._EmployeesRowdata, "Region");
		this.txtPostalCode.DataBindings.Add("Text", this._EmployeesRowdata, "PostalCode");
		this.txtCity.DataBindings.Add("Text", this._EmployeesRowdata, "City");
		this.txtStreet.DataBindings.Add("Text", this._EmployeesRowdata, "Address");
		this.txtFirstName.DataBindings.Add("Text", this._EmployeesRowdata, "FirstName");
		this.txtLastName.DataBindings.Add("Text", this._EmployeesRowdata, "LastName");
	} // end if((this._EmployeesRowdata != null))
	this.ResumeLayout(false);
} // end public void InitializeDataSource(assetm.Northwind.EmployeesRow employeesRowdata)

Depending on the selected approach, additional methods may be added to the form which perform functions such as:

• resetting the form to its initial state
• raising events upon user changes to control properties
• writing control property values back to the business class.

You can assign a business class to a form as follows:

1. Select the form in the Form Manager.
2. In the Form Detail pane, under Form Settings, click on the button with the three dots as shown below:
   
3. The Select Class dialog window opens. Click on the button with the three dots to browse to the assembly containing the desired business class.
   
4. Find the business class in the left pane and select it. Its properties are shown on the right.
5. Click OK to confirm your selection. The class is now bound to the form.
6. If you want to use Windows Forms data binding, select the "Use Data Binding" checkbox.