Extend the functionality of a TableAdapter

You can extend the functionality of a TableAdapter by adding code to the TableAdapter's partial class file.

The code that defines a TableAdapter is regenerated when any changes are made to the TableAdapter in the Dataset Designer, or when a wizard modifies the configuration of a TableAdapter. To prevent your code from being deleted during the regeneration of a TableAdapter, add code to the TableAdapter's partial class file.

Partial classes allow code for a specific class to be divided among multiple physical files. For more information, see Partial or partial (Type).

While TableAdapters are designed with the Dataset Designer, the TableAdapter classes that are generated are not nested classes of DataSet. TableAdapters are located in a namespace based on the name of the TableAdapter's associated dataset. For example, if your application contains a dataset named HRDataSet, the TableAdapters would be located in the HRDataSetTableAdapters namespace. (The naming convention follows this pattern: DatasetName + TableAdapters).

The following example assumes a TableAdapter named CustomersTableAdapteris in a project with NorthwindDataSet.

1. Add a new class to your project by going to the Project menu and selectingAdd Class.

2. Name the class CustomersTableAdapterExtended.

3. Select Add.

4. Replace the code with the correct namespace and partial class name for your project as follows:

   namespace NorthwindDataSetTableAdapters
   {
       public partial class CustomersTableAdapter
       {
           // Add user code here. For example:
           public override string ToString()
           {
               return "Overridden in the partial class.";
           }
       }
   }
   

   Namespace NorthwindDataSetTableAdapters
   
       Partial Class CustomersTableAdapter
   
           ' Add user code here. For example:
           Public Overrides Function ToString() As String
               Return "Overridden in the partial class."
           End Function
       End Class
   End Namespace
   

Fill datasets by using TableAdapters