' Put the next line into the Declarations section.
private myDataSet As DataSet 
 
Private Sub MakeDataTables()
    ' Run all of the functions. 
    MakeParentTable()
    MakeChildTable()
    MakeDataRelation()
    BindToDataGrid()
End Sub
'========================================================================================
Private Sub MakeParentTable()
    ' Create a new DataTable.
    Dim myDataTable As DataTable = new DataTable("ParentTable")
    ' Declare variables for DataColumn and DataRow objects.
    Dim myDataColumn As DataColumn 
    Dim myDataRow As DataRow 
 
    ' Create new DataColumn, set DataType, ColumnName and add to DataTable.
    myDataColumn = New DataColumn()
    myDataColumn.DataType = System.Type.GetType("System.Int32")
    myDataColumn.ColumnName = "id"
    myDataColumn.ReadOnly = True
    myDataColumn.Unique = True
    ' Add the Column to the DataColumnCollection.
    myDataTable.Columns.Add(myDataColumn)
 
    ' Create second column.
    myDataColumn = New DataColumn()
    myDataColumn.DataType = System.Type.GetType("System.String")
    myDataColumn.ColumnName = "ParentItem"
    myDataColumn.AutoIncrement = False
    myDataColumn.Caption = "ParentItem"
    myDataColumn.ReadOnly = False
    myDataColumn.Unique = False
    ' Add the column to the table.
    myDataTable.Columns.Add(myDataColumn)
 
    ' Make the ID column the primary key column.
    Dim PrimaryKeyColumns(0) As DataColumn
    PrimaryKeyColumns(0)= myDataTable.Columns("id")
    myDataTable.PrimaryKey = PrimaryKeyColumns
 
    ' Instantiate the DataSet variable.
    myDataSet = New DataSet()
    ' Add the new DataTable to the DataSet.
    myDataSet.Tables.Add(myDataTable)
 
    ' Create three new DataRow objects and add them to the DataTable
    Dim i As Integer
    For i = 0 to 2
       myDataRow = myDataTable.NewRow()
       myDataRow("id") = i
       myDataRow("ParentItem") = "ParentItem " + i.ToString()
       myDataTable.Rows.Add(myDataRow)
    Next i
End Sub
 
Private Sub MakeChildTable()
    ' Create a new DataTable.
    Dim myDataTable As DataTable = New DataTable("childTable")
    Dim myDataColumn As DataColumn 
    Dim myDataRow As DataRow 
 
    ' Create first column and add to the DataTable.
    myDataColumn = New DataColumn()
    myDataColumn.DataType= System.Type.GetType("System.Int32")
    myDataColumn.ColumnName = "ChildID"
    myDataColumn.AutoIncrement = True
    myDataColumn.Caption = "ID"
    myDataColumn.ReadOnly = True
    myDataColumn.Unique = True
    ' Add the column to the DataColumnCollection.
    myDataTable.Columns.Add(myDataColumn)
 
    ' Create second column.
    myDataColumn = New DataColumn()
    myDataColumn.DataType= System.Type.GetType("System.String")
    myDataColumn.ColumnName = "ChildItem"
    myDataColumn.AutoIncrement = False
    myDataColumn.Caption = "ChildItem"
    myDataColumn.ReadOnly = False
    myDataColumn.Unique = False
    myDataTable.Columns.Add(myDataColumn)
 
    ' Create third column.
    myDataColumn = New DataColumn()
    myDataColumn.DataType= System.Type.GetType("System.Int32")
    myDataColumn.ColumnName = "ParentID"
    myDataColumn.AutoIncrement = False
    myDataColumn.Caption = "ParentID"
    myDataColumn.ReadOnly = False
    myDataColumn.Unique = False
    myDataTable.Columns.Add(myDataColumn)
 
    myDataSet.Tables.Add(myDataTable)
    ' Create three sets of DataRow objects, five rows each, and add to DataTable.
    Dim i As Integer
    For i = 0 to 4
       myDataRow = myDataTable.NewRow()
       myDataRow("childID") = i
       myDataRow("ChildItem") = "Item " + i.ToString()
       myDataRow("ParentID") = 0 
       myDataTable.Rows.Add(myDataRow)
    Next i
    For i = 0 to 4
       myDataRow = myDataTable.NewRow()
       myDataRow("childID") = i + 5
       myDataRow("ChildItem") = "Item " + i.ToString()
       myDataRow("ParentID") = 1 
       myDataTable.Rows.Add(myDataRow)
    Next i
    For i = 0 to 4
       myDataRow = myDataTable.NewRow()
       myDataRow("childID") = i + 10
       myDataRow("ChildItem") = "Item " + i.ToString()
       myDataRow("ParentID") = 2 
       myDataTable.Rows.Add(myDataRow)
    Next i
End Sub
 
Private Sub MakeDataRelation()
    ' DataRelation requires two DataColumn (parent and child) and a name.
    Dim myDataRelation As DataRelation 
    Dim parentColumn As DataColumn 
    Dim childColumn As DataColumn 
    parentColumn = myDataSet.Tables("ParentTable").Columns("id")
    childColumn = myDataSet.Tables("ChildTable").Columns("ParentID")
    myDataRelation = new DataRelation("parent2Child", parentColumn, childColumn)
    myDataSet.Tables("ChildTable").ParentRelations.Add(myDataRelation)
End Sub
 
Private Sub BindToDataGrid()
    ' Instruct the DataGrid to bind to the DataSet, with the 
    ' ParentTable as the topmost DataTable.
    DataGrid1.SetDataBinding(myDataSet,"ParentTable")
End Sub