1. From the Visual Studio toolbox Common Controls tab, drag and drop a TreeView control onto the detail section of a report.
2. Notice that in the Properties window, the control is called CustomControl1.

1. Connect the report to the sample Nwind.mdb. The following steps use the Orders table from the NWind database. By default, in ActiveReports, the Nwind.mdb file is located at [User Documents folder]\ComponentOne Samples\ActiveReports 9\Data\Nwind.mdb.
2. From the Report Explorer, drag and drop the following fields onto the detail section of the report:
   • ShipCountry
   • ShipCity
   • CustomerID
   • EmployeeID
3. On the design surface, select all four TextBox controls, and in the Properties window, change their Visible property to False.

1. Right-click the design surface and select View Code to see the code view for the report.
2. Add the following code inside the report class to add a function to the report for adding nodes to the TreeView control.

The following examples show what the code for the function looks like.

To write the code in Visual Basic.NET

Private Function AddNodeToTreeView(ByVal colNodes As TreeNodeCollection, ByVal sText As String) As TreeNode
   Dim objTreeNode As TreeNode
   objTreeNode = New TreeNode(sText)
   colNodes.Add(objTreeNode)
   Return objTreeNode
End Function

To write the code in C#

private TreeNode AddNodeToTreeView(TreeNodeCollection colNodes, string sText) 
{ 
    TreeNode objTreeNode; 
    objTreeNode = new TreeNode(sText); 
    colNodes.Add(objTreeNode); 
    return objTreeNode; 
}

1. On the report design surface, double-click the detail section to create an event-handling method for the Detail_Format event.
2. Add the following code to the handler to access the TreeView properties and assign data from the hidden TextBox controls.

The following example shows what the code for the method looks like.

To write the code in Visual Basic.NET

To write the code in C#

//Type cast the custom control as a TreeView 
TreeView TreeView1 = new TreeView();
TreeView1 = (TreeView)this.customControl1.Control;
//Create a tree node 
TreeNode objCountryTreeNode;
//Assign the text from a hidden textbox to the node 
objCountryTreeNode = AddNodeToTreeView(TreeView1.Nodes, this.txtShipCountry1.Text);
//Add a second-level node 
AddNodeToTreeView(objCountryTreeNode.Nodes, this.txtShipCity1.Text);
//Expand the top-level node so the second-level node is in view 
objCountryTreeNode.Expand();
//Create a second top-level node 
TreeNode objCustomerTreeNode;
objCustomerTreeNode = AddNodeToTreeView(TreeView1.Nodes, this.txtCustomerID1.Text);
AddNodeToTreeView(objCustomerTreeNode.Nodes, this.txtEmployeeID1.Text);
objCustomerTreeNode.Expand();