Walkthrough: Creating a Master/Detail Form Using Two Windows Forms DataGridView Controls
One of the most common scenarios for using the DataGridView control is the master/detail form, in which a parent/child relationship between two database tables is displayed. Selecting rows in the master table causes the detail table to update with the corresponding child data.
Implementing a master/detail form is easy using the interaction between the DataGridView control and the BindingSource component. In this walkthrough, you will build the form using two DataGridView controls and two BindingSource components. The form will show two related tables in the Northwind SQL Server sample database: Customers and Orders. When you are finished, you will have a form that shows all the customers in the database in the master DataGridView and all the orders for the selected customer in the detail DataGridView.
To copy the code in this topic as a single listing, see How to: Create a Master/Detail Form Using Two Windows Forms DataGridView Controls.
To create a master/detail form
Create a class that derives from Form and contains two DataGridView controls and two BindingSource components. The following code provides basic form initialization and includes a Main method. If you use the Visual Studio designer to create your form, you can use the designer generated code instead of this code, but be sure to use the names shown in the variable declarations here.
Implement a method in your form's class definition for handling the detail of connecting to the database. This example uses a GetData method that populates a DataSet object, adds a DataRelation object to the data set, and binds the BindingSource components. Be sure to set the connectionString variable to a value that is appropriate for your database.
Storing sensitive information, such as a password, within the connection string can affect the security of your application. Using Windows Authentication (also known as integrated security) is a more secure way to control access to a database. For more information, see Protecting Connection Information.
Implement a handler for your form's Load event that binds the DataGridView controls to the BindingSource components and calls the GetData method. The following example includes code that resizes DataGridView columns to fit the displayed data.
You can now test the form to make sure it behaves as expected.
To test the form
Compile and run the application.
You will see two DataGridView controls, one above the other. On top are the customers from the Northwind Customers table, and at the bottom are the Orders corresponding to the selected customer. As you select different rows in the upper DataGridView, the contents of the lower DataGridView change accordingly.
Change border and header styles. For more information, see How to: Change the Border and Gridline Styles in the Windows Forms DataGridView Control.
Enable or restrict user input to the DataGridView control. For more information, see How to: Prevent Row Addition and Deletion in the Windows Forms DataGridView Control, and How to: Make Columns Read-Only in the Windows Forms DataGridView Control.
Validate user input to the DataGridView control. For more information, see Walkthrough: Validating Data in the Windows Forms DataGridView Control.
Handle very large data sets using virtual mode. For more information, see Walkthrough: Implementing Virtual Mode in the Windows Forms DataGridView Control.
Customize the appearance of cells. For more information, see How to: Customize the Appearance of Cells in the Windows Forms DataGridView Control and How to: Set Default Cell Styles for the Windows Forms DataGridView Control.