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Connect to an Access database in .NET Framework applications

Note

Datasets and related classes are legacy .NET Framework technologies from the early 2000s that enable applications to work with data in memory while the applications are disconnected from the database. The technologies are especially useful for applications that enable users to modify data and persist the changes back to the database. Although datasets have proven to be a very successful technology, we recommend that new .NET applications use Entity Framework Core. Entity Framework provides a more natural way to work with tabular data as object models, and it has a simpler programming interface.

You can connect to an Access database (either an .mdb file or an .accdb file) by using Visual Studio. After you define the connection, the data appears in the Data Sources window. From there, you can drag tables or views onto your design surface.

Note

If you're using Visual Studio to connect to Access databases, you will need to be aware that versions of Visual Studio prior to Visual Studio 2022 are all 32-bit processes. This means some of the data tools in Visual Studio 2019 and earlier will only be able to connect to Access databases using 32-bit data providers.

If you're using Visual Studio 2022 to connect to Access databases, you will need to be aware that Visual Studio 2022 is now a 64-bit process. This means some of the data tools in Visual Studio will not be able to connect to Access databases using 32-bit data providers.

If you need to maintain 32-bit applications that connect to Access databases, you will still be able to build and run the application with Visual Studio 2022. However, if you need to use any of the Visual Studio Data Tools such as Server Explorer, Data Source Wizard, or the DataSet Designer, you will need to use an earlier version of Visual Studio that is still a 32-bit process. The last version of Visual Studio that was a 32-bit process was Visual Studio 2019.

If you plan on converting the project to be a 64-bit process, it's recommended that you use the 64-bit Microsoft Access database Engine, also called Access Connectivity Engine (ACE). Please see OLE DB Provider for Jet and ODBC driver are 32-bit versions only for more information.

Prerequisites

To use these procedures, you need:

  • Visual Studio
  • A Windows Forms or WPF project
  • Either an Access database (.accdb file), or an Access 2000-2003 database (.mdb file). Follow the procedure that corresponds to your file type.

Create a dataset for an .accdb file

Connect to databases created with Microsoft 365, Access 2016, Access 2013, Access 2010, or Access 2007 by using the following procedure.

  1. Open a Windows Forms or WPF application project in Visual Studio.

  2. To open the Data Sources window, press Ctrl+Q, enter "data" in the search box, and choose Data Sources window. Or on the View menu, select Other Windows > Data Sources. Or on the keyboard, press Shift+Alt+D.

    Screenshot of Data Sources in search box

  3. In the Data Sources window, click Add New Data Source.

    The Data Source Configuration Wizard opens.

    Screenshot showing Data Source Configuration Wizard

  4. Select Database on the Choose a Data Source Type page, and then select Next.

  5. Select Dataset on the Choose a Database Model page, and then select Next.

    Screenshot of Choose a Database Model page

  6. On the Choose your Data Connection page, select New Connection to configure a new data connection.

    Screenshot of Choose your Data Connection page

    The Add Connection dialog box opens.

    Screenshot of Add Connection dialog box

  7. If Data source is not set to Microsoft Access Database File, select the Change button.

    The Change Data Source dialog box opens. In the list of data sources, choose Microsoft Access Database File. The option .NET Framework Data Provider for OLE DB is already preselected. Choose OK.

    Screenshot of Choose Data Source dialog box

  8. Choose Browse next to Database file name, and then navigate to your .accdb file and choose Open.

    Note

    If the bitness (32-bit or 64-bit) of Microsoft Office and Visual Studio do not match, you will see an error while connecting to an Access database. In Visual Studio 2019, you will get an error that the database provider is not registered. In Visual Studio 2022, you will see an error that you can't connect to a 32-bit data provider. To resolve this error, make sure that if you are using a 32-bit version of Office, you are using Visual Studio 2019 or earlier; for a 64-bit version of Office, you need Visual Studio 2022 or later.

  9. Enter a user name and password (if necessary), and then choose OK.

  10. Select Next on the Choose your Data Connection page.

    You might get a dialog box telling you the data file is not in your current project. Select Yes or No.

  11. Select Next on the Save connection string to the Application Configuration file page.

    Screenshot of page

  12. Expand the Tables node on the Choose your Database Objects page.

    Screenshot of Choose your Database Objects page

  13. Select the tables or views you want to include in your dataset, and then select Finish.

    The dataset is added to your project, and the tables and views appear in the Data Sources window.

    Screenshot of Data Sources Window, populated with database objects

  14. On 64-bit machines with the 64-bit Access database engine, you need to ensure that the application runs as a 64-bit application. Open the project properties (press Alt+Enter or right-click on the project node, and select Properties). In the Build tab, clear the Prefer 32-bit checkbox.

Create a dataset for an .accdb file

Connect to databases created with Microsoft 365, Access 2016, Access 2013, Access 2010, or Access 2007 by using the following procedure.

  1. Open a Windows Forms or WPF application project in Visual Studio.

  2. To open the Data Sources window, press Ctrl+Q, enter "data" in the search box, and choose Data Sources window. Or on the View menu, select Other Windows > Data Sources. Or on the keyboard, press Shift+Alt+D.

    View Other Windows Data Sources

  3. In the Data Sources window, click Add New Data Source.

    The Data Source Configuration Wizard opens.

  4. Select Database on the Choose a Data Source Type page, and then select Next.

  5. Select Dataset on the Choose a Database Model page, and then select Next.

    Screenshot of Choose a Database Model page

  6. On the Choose your Data Connection page, select New Connection to configure a new data connection.

    Screenshot of Choose your Data Connection page

    The Add Connection dialog box opens.

    Screenshot of Add Connection dialog box

  7. If Data source is not set to Microsoft Access Database File, select the Change button.

    The Change Data Source dialog box opens. In the list of data sources, choose Microsoft Access Database File. The option .NET Framework Data Provider for OLE DB is already preselected. Choose OK.

    Screenshot of Choose Data Source dialog box

  8. Choose Browse next to Database file name, and then navigate to your .accdb file and choose Open.

    Note

    If the bitness (32-bit or 64-bit) of Microsoft Office and Visual Studio do not match, you will see an error while connecting to an Access database. In Visual Studio 2019, you will get an error that the database provider is not registered. In Visual Studio 2022, you will see an error that you can't connect to a 32-bit data provider. To resolve this error, make sure that if you are using a 32-bit version of Office, you are using Visual Studio 2019 or earlier; for a 64-bit version of Office, you need Visual Studio 2022 or later.

  9. Enter a user name and password (if necessary), and then choose OK.

  10. Select Next on the Choose your Data Connection page.

    You might get a dialog box telling you the data file is not in your current project. Select Yes or No.

  11. Select Next on the Save connection string to the Application Configuration file page.

    Screenshot of page

  12. Expand the Tables node on the Choose your Database Objects page.

  13. Select the tables or views you want to include in your dataset, and then select Finish.

    The dataset is added to your project, and the tables and views appear in the Data Sources window.

Create a dataset for an .mdb file

Connect to databases created with Access 2000-2003 by using the following procedure.

  1. Open a Windows Forms or WPF application project in Visual Studio.

  2. On the View menu, select Other Windows > Data Sources.

  3. In the Data Sources window, click Add New Data Source.

    The Data Source Configuration Wizard opens.

  4. Select Database on the Choose a Data Source Type page, and then select Next.

  5. Select Dataset on the Choose a Database Model page, and then select Next.

  6. On the Choose your Data Connection page, select New Connection to configure a new data connection.

  7. If the data source is not Microsoft Access Database File (OLE DB), select Change to open the Change Data Source dialog box and select Microsoft Access Database File, and then select OK.

  8. In the Database file name, specify the path and name of the .mdb file you want to connect to, and then select OK.

    Add Connection Access database File

  9. Select Next on the Choose your Data Connection page.

  10. Select Next on the Save connection string to the Application Configuration file page.

  11. Expand the Tables node on the Choose your Database Objects page.

  12. Select whatever tables or views you want in your dataset, and then select Finish.

    The dataset is added to your project, and the tables and views appear in the Data Sources window.

View the generated code

The data tools are configured to generate a lot of code automatically when you perform certain operations in the Form Designer. For example, when you drag and drop a table onto the form, a DataGridView is added and code is created to hook up the data with the control. You can view this code in the *.Designer.cs file. Visual Studio adds a number of private members:

private Database11DataSet database11DataSet;
private System.Windows.Forms.BindingSource ordersBindingSource;
private Database11DataSetTableAdapters.OrdersTableAdapter ordersTableAdapter;
private Database11DataSetTableAdapters.TableAdapterManager tableAdapterManager;
private System.Windows.Forms.BindingNavigator ordersBindingNavigator;
private System.Windows.Forms.ToolStripButton bindingNavigatorAddNewItem;
private System.Windows.Forms.ToolStripLabel bindingNavigatorCountItem;
private System.Windows.Forms.ToolStripButton bindingNavigatorDeleteItem;
private System.Windows.Forms.ToolStripButton bindingNavigatorMoveFirstItem;
private System.Windows.Forms.ToolStripButton bindingNavigatorMovePreviousItem;
private System.Windows.Forms.ToolStripSeparator bindingNavigatorSeparator;
private System.Windows.Forms.ToolStripTextBox bindingNavigatorPositionItem;
private System.Windows.Forms.ToolStripSeparator bindingNavigatorSeparator1;
private System.Windows.Forms.ToolStripButton bindingNavigatorMoveNextItem;
private System.Windows.Forms.ToolStripButton bindingNavigatorMoveLastItem;
private System.Windows.Forms.ToolStripSeparator bindingNavigatorSeparator2;
private System.Windows.Forms.ToolStripButton ordersBindingNavigatorSaveItem;
private System.Windows.Forms.DataGridView ordersDataGridView;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn1;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn2;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn3;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn4;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn5;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn6;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn7;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn8;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn9;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn10;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn11;
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn12;

If you expand the hidden region, you can see that Visual Studio also adds a large amount of code to set up the DataGridView control with data binding to the table you dragged to the form.

Also, in the main form code-behind file, Visual Studio adds code that processes the save action to save interactive changes to the data, and the code that loads the table into the table adapter.

private void ordersBindingNavigatorSaveItem_Click(object sender, EventArgs e)
{
    this.Validate();
    this.ordersBindingSource.EndEdit();
    this.tableAdapterManager.UpdateAll(this.database11DataSet);

}

private void Form1_Load(object sender, EventArgs e)
{
   // TODO: This line of code loads data into the 'database11DataSet.Orders' table. You can move, or remove it, as needed.
   this.ordersTableAdapter.Fill(this.database11DataSet.Orders);
}

Congratulations! With a little help from Visual Studio, you've created a form-based editing experience for an Access data table.

Next steps

The dataset that you just created is available in the Data Sources window. You can now perform any of the following tasks: