Create a Windows Forms user control that supports simple data binding

When displaying data on forms in Windows applications, you can choose existing controls from the Toolbox, or you can author custom controls if your application requires functionality that is not available in the standard controls. This walkthrough shows how to create a control that implements the DefaultBindingPropertyAttribute. Controls that implement the DefaultBindingPropertyAttribute can contain one property that can be bound to data. Such controls are similar to a TextBox or CheckBox.

For more information on control authoring, see Developing Windows Forms Controls at Design Time.

When authoring controls for use in data-binding scenarios, you should implement one of the following data-binding attributes:

This walkthrough creates a simple control that displays data from a single column in a table. This example uses the Phone column of the Customers table from the Northwind sample database. The simple user control will display customers' phone numbers in a standard phone-number format, by using a MaskedTextBox and setting the mask to a phone number.

During this walkthrough, you will learn how to:

• Create a new Windows Application.

• Add a new User Control to your project.

• Visually design the user control.

• Implement the DefaultBindingProperty attribute.

• Create a dataset with the Data Source Configuration wizard.

• Set the Phone column in the Data Sources window to use the new control.

• Create a form to display data in the new control.

Prerequisites

In order to complete this walkthrough, you will need:

• Access to the Northwind sample database.

Create a Windows Application

The first step is to create a Windows Application.

To create the new Windows project

1. In Visual Studio, from the File menu, create a new Project.

2. Name the project SimpleControlWalkthrough.

3. Select Windows Application and click OK. For more information, see Client Applications.

   The SimpleControlWalkthrough project is created, and added to Solution Explorer.

Add a user control to the project

This walkthrough creates a simple data-bindable control from a User Control, so add a User Control item to the SimpleControlWalkthrough project.

To add a user control to the project

1. From the Project menu, choose Add User Control.

2. Type PhoneNumberBox in the Name area, and click Add.

   The PhoneNumberBox control is added to Solution Explorer, and opens in the designer.

Design the PhoneNumberBox control

This walkthrough expands upon the existing MaskedTextBox to create the PhoneNumberBox control.

To design the PhoneNumberBox control

1. Drag a MaskedTextBox from the Toolbox onto the user control's design surface.

2. Select the smart tag on the MaskedTextBox you just dragged, and choose Set Mask.

3. Select Phone number in the Input Mask dialog box, and click OK to set the mask.

Add the required data-binding attribute

For simple controls that support databinding, implement the DefaultBindingPropertyAttribute.

To implement the DefaultBindingProperty attribute

1. Switch the PhoneNumberBox control to code view. (On the View menu, choose Code.)

2. Replace the code in the PhoneNumberBox with the following:

   using System.Windows.Forms;
   
   namespace CS
   {
       [System.ComponentModel.DefaultBindingProperty("PhoneNumber")]
       public partial class PhoneNumberBox : UserControl
       {
           public string PhoneNumber
           {
               get{ return maskedTextBox1.Text; }
               set{ maskedTextBox1.Text = value; }
           }
   
           public PhoneNumberBox()
           {
               InitializeComponent();
           }
       }
   }
   

   <System.ComponentModel.DefaultBindingProperty("PhoneNumber")>
   Public Class PhoneNumberBox
   
       Public Property PhoneNumber() As String
           Get
               Return MaskedTextBox1.Text
           End Get
           Set(ByVal value As String)
               MaskedTextBox1.Text = value
           End Set
       End Property
   End Class
   

3. From the Build menu, choose Build Solution.

Create a data source from your database

This step uses the Data Source Configuration wizard to create a data source based on the Customers table in the Northwind sample database. You must have access to the Northwind sample database to create the connection.

To create the data source

1. On the Data menu, click Show Data Sources.

2. In the Data Sources window, select Add New Data Source to start the Data Source Configuration wizard.

3. On the Choose a Data Source Type page, select Database, and then click Next.

4. On the Choose your Data Connection page, do one of the following:

   • If a data connection to the Northwind sample database is available in the drop-down list, select it.

   • Select New Connection to launch the Add/Modify Connection dialog box.

5. If your database requires a password, select the option to include sensitive data, and then click Next.

6. On the Save connection string to the Application Configuration file page, click Next.

7. On the Choose your Database Objects page, expand the Tables node.

8. Select the Customers table, and then click Finish.

   The NorthwindDataSet is added to your project, and the Customers table appears in the Data Sources window.

Set the phone column to use the PhoneNumberBox control

Within the Data Sources window, you can set the control to be created prior to dragging items onto your form.

To set the phone column to bind to the PhoneNumberBox control

1. Open Form1 in the designer.

2. Expand the Customers node in the Data Sources window.

3. Click the drop-down arrow on the Customers node, and choose Details from the control list.

4. Click the drop-down arrow on the Phone column, and choose Customize.

5. Select the PhoneNumberBox from the list of Associated Controls in the Data UI Customization Options dialog box.

6. Click the drop-down arrow on the Phone column, and choose PhoneNumberBox.

Addcontrols to the form

You can create the data-bound controls by dragging items from the Data Sources window onto the form.

To create data-bound controls on the form

• Drag the main Customers node from the Data Sources window onto the form, and verify that the PhoneNumberBox control is used to display the data in the Phone column.

  Data-bound controls with descriptive labels appear on the form, along with a tool strip (BindingNavigator) for navigating records. A NorthwindDataSet, CustomersTableAdapter, BindingSource, and BindingNavigator appear in the component tray.

Run the application

To run the application

• Press F5 to run the application.

Next Steps

Depending on your application requirements, there are several steps you may want to perform after creating a control that supports data binding. Some typical next steps include:

• Placing your custom controls in a control library so you can reuse them in other applications.

• Creating controls that support more complex data-binding scenarios. For more information, see Create a Windows Forms user control that supports complex data binding and Create a Windows Forms user control that supports lookup data binding.

See Also

Bind Windows Forms controls to data in Visual Studio Set the control to be created when dragging from the Data Sources window