using DevExpress.XtraTreeList;
using DevExpress.XtraEditors;

private void ShowTreeListPreview(TreeList treeList) {
    if (!treeList.IsPrintingAvailable) {
        XtraMessageBox.Show("Print library not found", "Error");
        return;
    }
    treeList.ShowRibbonPrintPreview();
}

private void PrintTreeList(TreeList treeList) {
    if (!treeList.IsPrintingAvailable) {
        XtraMessageBox.Show("Print library not found", "Error");
        return;
    }
    treeList.Print();
}

Imports DevExpress.XtraTreeList
Imports DevExpress.XtraEditors

Sub ShowTreeListPreview(ByVal treeList As TreeList)
   If Not treeList.IsPrintingAvailable Then
      XtraMessageBox.Show("Print library not found", "Error")
      Return
   End If
   treeList.ShowRibbonPrintPreview()
End Sub

Sub PrintTreeList(ByVal treeList As TreeList)
   If Not treeList.IsPrintingAvailable Then
      XtraMessageBox.Show("Print library not found", "Error")
      Return
   End If
   treeList.Print()
End Sub

treeList1.OptionsPrint.UsePrintStyles = true;
treeList1.AppearancePrint.EvenRow.BackColor = Color.FromArgb(255, 192, 128);

TreeList1.OptionsPrint.UsePrintStyles = True
TreeList1.AppearancePrint.EvenRow.BackColor = Color.FromArgb(255, 192, 128)

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

treeList1.OptionsView.ShowSummaryFooter = true;
colBUDGET.SummaryFooter = DevExpress.XtraTreeList.SummaryItemType.Custom;
colBUDGET.SummaryFooterStrFormat = "Departments exceeded the budget: {0}";
treeList1.GetPrintCustomSummaryValue += (s, e) => {
    if (e.IsSummaryFooter && e.Column == colBUDGET) {
        TreeListExceedLimitOperation operation =
          new TreeListExceedLimitOperation("BUDGET", 500000);
        treeList1.NodesIterator.DoOperation(operation);
        e.CustomValue = operation.Result;
    }
};
treeList1.GetCustomSummaryValue += (s, e) => {
    if (e.IsSummaryFooter && e.Column == colBUDGET) {
        TreeListExceedLimitOperation operation =
          new TreeListExceedLimitOperation("BUDGET", 100000);
        treeList1.NodesIterator.DoOperation(operation);
        e.CustomValue = operation.Result;
    }
};

// An operation that counts the number of nodes
// that have a specific value in a specific column
public class TreeListExceedLimitOperation : TreeListOperation {
    private string fieldName;
    private int upperLimit;
    private int value;

    public TreeListExceedLimitOperation(string fieldName, int upperLimit) {
        this.fieldName = fieldName;
        this.upperLimit = upperLimit;
        value = 0;
    }
    // This method is called for each node in the control.
    public override void Execute(TreeListNode node) {
        int nodeValue = Convert.ToInt32(node[fieldName]);
        if (nodeValue > upperLimit)
            value++;
    }
    public int Result {
        get { return value; }
    }
}

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

treeList1.OptionsView.ShowSummaryFooter = True
colBUDGET.SummaryFooter = DevExpress.XtraTreeList.SummaryItemType.Custom
colBUDGET.SummaryFooterStrFormat = "Departments exceeded the budget: {0}"
AddHandler treeList1.GetPrintCustomSummaryValue, Sub(s, e)
    If e.IsSummaryFooter AndAlso e.Column Is colBUDGET Then
        Dim operation As New TreeListExceedLimitOperation("BUDGET", 500000)
        treeList1.NodesIterator.DoOperation(operation)
        e.CustomValue = operation.Result
    End If
End Sub
AddHandler treeList1.GetCustomSummaryValue, Sub(s, e)
    If e.IsSummaryFooter AndAlso e.Column Is colBUDGET Then
        Dim operation As New TreeListExceedLimitOperation("BUDGET", 100000)
        treeList1.NodesIterator.DoOperation(operation)
        e.CustomValue = operation.Result
    End If
End Sub

' An operation that counts the number of nodes
' that have a specific value in a specific column
Public Class TreeListExceedLimitOperation
    Inherits TreeListOperation

    Private fieldName As String
    Private upperLimit As Integer
    Private value As Integer

    Public Sub New(ByVal fieldName As String, ByVal upperLimit As Integer)
        Me.fieldName = fieldName
        Me.upperLimit = upperLimit
        value = 0
    End Sub
    ' This method is called for each node in the control.
    Public Overrides Sub Execute(ByVal node As TreeListNode)
        Dim nodeValue As Integer = Convert.ToInt32(node(fieldName))
        If nodeValue > upperLimit Then
            value += 1
        End If
    End Sub
    Public ReadOnly Property Result() As Integer
        Get
            Return value
        End Get
    End Property
End Class

using DevExpress.XtraTreeList;

treeList1.OptionsView.ShowPreview = true;

private void treeList1_GetPreviewText(object sender, GetPreviewTextEventArgs e) {
   e.PreviewText = "Office location: " + e.Node["Location"].ToString() + 
     "; Contact phone: " + e.Node["Phone"].ToString();
}

private void treeList1_GetPrintPreviewText(object sender, GetPreviewTextEventArgs e) {
   e.PreviewText = "Office location: " + e.Node["Location"].ToString() + 
     "\nContact phone: " + e.Node["Phone"].ToString();
}

Imports DevExpress.XtraTreeList

treeList1.OptionsView.ShowPreview = True

Private Sub TreeList1_GetPreviewText(ByVal sender As Object, _
ByVal e As GetPreviewTextEventArgs) Handles TreeList1.GetPreviewText
   e.PreviewText = "Office location: " + e.Node("Location") + _
      "; Contact phone: " + e.Node("Phone")
End Sub

Private Sub TreeList1_GetPrintPreviewText(ByVal sender As Object, _
ByVal e As GetPreviewTextEventArgs) Handles TreeList1.GetPrintPreviewText
   e.PreviewText = "Office location: " + e.Node("Location") + _
     vbCrLf + "Contact phone: " + e.Node("Phone")
End Sub