TreeList.AppendNode(Object, Int32, Object) Method

Adds a TreeListNode containing the specified values to the XtraTreeList.

Namespace: DevExpress.XtraTreeList

Assembly: DevExpress.XtraTreeList.v23.2.dll

NuGet Packages: DevExpress.Win.Navigation, DevExpress.Win.TreeList

Declaration

C#

public virtual TreeListNode AppendNode(
    object nodeData,
    int parentNodeId,
    object tag
)

VB.NET

Public Overridable Function AppendNode(
    nodeData As Object,
    parentNodeId As Integer,
    tag As Object
) As TreeListNode

Parameters

Name	Type	Description
nodeData	Object	An array of values or a DataRow object, used to initialize the created node’s cells.
parentNodeId	Int32	An integer value specifying the identifier of the parent node.
tag	Object	An object that contains information associated with the Tree List node. This value is assigned to the TreeListNode.Tag property.

Returns

Type	Description
TreeListNode	A TreeListNode object or descendant representing the added node.

Remarks

Use the AppendNode method to append a new node to the specified node’s child collection. Use the parentNodeId parameter to specify the parent node by its identifier. Node identifiers are returned by the TreeListNode.Id property. To add a node at the root level, the parentNodeId parameter must be set to the value of the TreeList.RootValue property.

The nodeData parameter specifies data for the columns of the node that is to be created. This parameter value can be an array of values or a DataRow object. The number and order of items in the array/DataRow object must match the number and order of Tree List columns.

Refer to the Nodes topic to learn more.

Example

The following code shows how to manually populate a TreeList control with nodes in unbound mode.

To add nodes in unbound mode, utilize the TreeList.AppendNode method. Data that is passed to this method must match the TreeList columns. So, the TreeList columns are created before the nodes are created.

Note that calls to the methods used to create nodes are wrapped with the TreeList.BeginUnboundLoad and TreeList.EndUnboundLoad methods. This reduces the control’s updates to a minimum, and thus improves performance.

The following image displays the result.

C#

using DevExpress.XtraTreeList;
using DevExpress.XtraTreeList.Columns;
using DevExpress.XtraTreeList.Nodes;

private void Form1_Load(object sender, EventArgs e) {
    CreateColumns(treeList1);
    CreateNodes(treeList1);
}

private void CreateColumns(TreeList tl) {
    // Create three columns
    tl.BeginUpdate();
    TreeListColumn col1 = tl.Columns.Add();
    col1.FieldName = "Customer";
    col1.Caption = "Customer";
    col1.VisibleIndex = 0;
    TreeListColumn col2 = tl.Columns.Add();
    col2.FieldName = "Location";
    col2.Caption = "Location";
    col2.VisibleIndex = 1;
    TreeListColumn col3 = tl.Columns.Add();
    col3.FieldName = "Phone";
    col3.Caption = "Phone";
    col3.VisibleIndex = 2;
    tl.EndUpdate();
}

private void CreateNodes(TreeList tl) {
    tl.BeginUnboundLoad();
    // Create a root node
    TreeListNode parentForRootNodes = null;
    TreeListNode rootNode = tl.AppendNode(
        new object[] { "Alfreds Futterkiste", "Germany, Obere Str. 57", "030-0074321" },
        parentForRootNodes);
    // Create a child of the rootNode
    tl.AppendNode(new object[] { "Suyama, Michael", "Obere Str. 55", "030-0074263" }, rootNode);
    // Create more nodes
    // ...
    tl.EndUnboundLoad();
}

VB.NET

Imports DevExpress.XtraTreeList
Imports DevExpress.XtraTreeList.Columns
Imports DevExpress.XtraTreeList.Nodes

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    CreateColumns(treeList1)
    CreateNodes(treeList1)
End Sub

Private Sub CreateColumns(ByVal tl As TreeList)
    ' Create three columns
    tl.BeginUpdate()
    Dim col1 As TreeListColumn = tl.Columns.Add()
    col1.FieldName = "Customer"
    col1.Caption = "Customer"
    col1.VisibleIndex = 0
    Dim col2 As TreeListColumn = tl.Columns.Add()
    col2.FieldName = "Location"
    col2.Caption = "Location"
    col2.VisibleIndex = 1
    Dim col3 As TreeListColumn = tl.Columns.Add()
    col3.FieldName = "Phone"
    col3.Caption = "Phone"
    col3.VisibleIndex = 2
    tl.EndUpdate()
End Sub

Private Sub CreateNodes(ByVal tl As TreeList)
    tl.BeginUnboundLoad()
    ' Create a root node
    Dim parentForRootNodes As TreeListNode = Nothing
    Dim rootNode As TreeListNode = tl.AppendNode(New Object() { "Alfreds Futterkiste", "Germany, Obere Str. 57", "030-0074321" }, parentForRootNodes)
    ' Create a child of the rootNode
    tl.AppendNode(New Object() { "Suyama, Michael", "Obere Str. 55", "030-0074263" }, rootNode)
    ' Create more nodes
    ' ...
    tl.EndUnboundLoad()
End Sub