How to create a watermark only to the selected page in word

This link Add Watermark in C#|Aspose.Words for .NET has provision to add watermark in whole document but we need to add water mark to specific pages only such as 6 page or 8 page in the document. Can you help me to achieve this functionality using Aspose.Word library.

@mehtabcompunnel,

You can build logic on the following code to get the desired output:

Document doc = new Document("E:\\temp\\in.docx");

Node[] runs = doc.GetChildNodes(NodeType.Run, true).ToArray();
for (int i = 0; i < runs.Length; i++)
{
    Run run = (Run)runs[i];
    int length = run.Text.Length;

    Run currentNode = run;
    for (int x = 1; x < length; x++)
    {
        currentNode = SplitRun(currentNode, 1);
    }
}

DocumentBuilder builder = new DocumentBuilder(doc);
PageSetup ps = builder.PageSetup;

NodeCollection smallRuns = doc.GetChildNodes(NodeType.Run, true);
LayoutCollector collector = new LayoutCollector(doc);

int pageIndex = 8;
foreach (Run run in smallRuns)
{
    if (collector.GetStartPageIndex(run) == pageIndex)
    {
        Shape watermark = new Shape(doc, Aspose.Words.Drawing.ShapeType.TextPlainText);
        watermark.RelativeHorizontalPosition = RelativeHorizontalPosition.Page;
        watermark.RelativeVerticalPosition = RelativeVerticalPosition.Page;

        watermark.Width = 300;
        watermark.Height = 70;
        watermark.HorizontalAlignment = HorizontalAlignment.Center;
        watermark.VerticalAlignment = VerticalAlignment.Center;

        watermark.Rotation = -40;
        watermark.Fill.Color = Color.Gray;
        watermark.StrokeColor = Color.Gray;

        watermark.TextPath.Text = "watermarkText";
        watermark.TextPath.FontFamily = "Arial";

        watermark.Name = string.Format("WaterMark_{0}", Guid.NewGuid());
        watermark.WrapType = WrapType.None;

        builder.MoveTo(run);
        builder.InsertNode(watermark);

        break;
    }
}

doc.Save("E:\\temp\\19.1.docx");

private static Run SplitRun(Run run, int position)
{
    Run afterRun = (Run)run.Clone(true);
    afterRun.Text = run.Text.Substring(position);
    run.Text = run.Text.Substring((0), (0) + (position));
    run.ParentNode.InsertAfter(afterRun, run);
    return afterRun;
}