--- title: Bind Controls to DBNull Database Values ms.date: "03/30/2017" dev_langs: - "csharp" - "vb" helpviewer_keywords: - "BindingSource component [Windows Forms], binding to DBNull values" - "examples [Windows Forms], BindingSource component" - "controls [Windows Forms], binding to DBNull values" ms.assetid: 96494e6f-5f40-4f83-af97-bbd7192c2af8 --- # How to: Bind Windows Forms Controls to DBNull Database Values When you bind Windows Forms controls to a data source and the data source returns a value, you can substitute an appropriate value without handling, formatting, or parsing events. The property will convert to a specified object when formatting or parsing the data source values. ## Example The following example demonstrates how to bind a value in two different situations. The first demonstrates how to set the for a string property; the second demonstrates how to set the for an image property. [!code-csharp[System.Windows.Forms.BindingDBNull#1](~/samples/snippets/csharp/VS_Snippets_Winforms/System.Windows.Forms.BindingDBNull/CS/form1.cs#1)] [!code-vb[System.Windows.Forms.BindingDBNull#1](~/samples/snippets/visualbasic/VS_Snippets_Winforms/System.Windows.Forms.BindingDBNull/VB/form1.vb#1)] The types of the bound property and the property must be the same or an error will result, and no further values will be processed. In this situation, an exception will not be thrown. ## Compiling the Code This example requires: - References to the System, System.Data, System.Drawing and System.Windows.Forms assemblies. ## See also - [BindingSource Component](bindingsource-component.md) - [How to: Handle Errors and Exceptions that Occur with Databinding](how-to-handle-errors-and-exceptions-that-occur-with-databinding.md) - [How to: Bind a Windows Forms Control to a Type](how-to-bind-a-windows-forms-control-to-a-type.md)