public class PdfTextMarkupAnnotationData :
    PdfMarkupAnnotationData

Public Class PdfTextMarkupAnnotationData
    Inherits PdfMarkupAnnotationData

using DevExpress.Pdf;
//...
using (PdfDocumentProcessor processor = new PdfDocumentProcessor())
{
    //Load a document:
    processor.LoadDocument("..\\..\\Document.pdf");

    //Add a text markup annotation at the first page:
    PdfTextMarkupAnnotationData textMarkup =
    processor.AddTextMarkupAnnotation(1, new PdfRectangle(90, 100, 240, 230),
    PdfTextMarkupAnnotationType.Highlight);

    if (textMarkup != null)
    {
        //Specify the annotation properties:
        textMarkup.Author = "Bill Smith";
        textMarkup.Contents = "Important!";
        textMarkup.Color = new PdfRGBColor(0.8, 0.2, 0.1);
    }

    //Add a sticky note at the first page:
    PdfTextAnnotationData textAnnotation =
    processor.AddTextAnnotation(1, new PdfPoint(100, 300));

    //Specify the annotation parameters:
    textAnnotation.Author = "Nancy Davolio";
    textAnnotation.Checked = true;
    textAnnotation.Color = new PdfRGBColor(0.8, 0.2, 0.1);
    textAnnotation.Contents = "Please proofread this document";
    textAnnotation.IconName = PdfTextAnnotationIconName.Check;

    //Save the result:
    processor.SaveDocument("..\\..\\Result.pdf");
}

Imports DevExpress.Pdf
'...
Using processor As New PdfDocumentProcessor()

    'Load a document:
    processor.LoadDocument("..\..\Document.pdf")

    'Add a text markup annotation on the first page:
    Dim textMarkup As PdfTextMarkupAnnotationData =
    processor.AddTextMarkupAnnotation(1, New PdfRectangle(90, 100, 240, 230), 
    PdfTextMarkupAnnotationType.Highlight)

    If textMarkup IsNot Nothing Then
        'Specify the annotation properties:
        textMarkup.Author = "Bill Smith"
        textMarkup.Contents = "Important!"
        textMarkup.Color = New PdfRGBColor(0.8, 0.2, 0.1)
    End If

    'Add a sticky note at the first page:
    Dim textAnnotation As PdfTextAnnotationData =
    processor.AddTextAnnotation(1, New PdfPoint(100, 300))

    'Specify the annotation parameters:
    textAnnotation.Author = "Nancy Davolio"
    textAnnotation.Checked = True
    textAnnotation.Color = New PdfRGBColor(0.8, 0.2, 0.1)
    textAnnotation.Contents = "Please proofread this document"
    textAnnotation.IconName = PdfTextAnnotationIconName.Check

    'Save the result:
    processor.SaveDocument("..\..\Result.pdf")
End Using

using DevExpress.Pdf;
using System;
using System.Collections.Generic;
//...
private static void EditAnnotations(PdfDocumentProcessor processor)
{
    //Retrieve annotations made by the specified author:
    var textMarkups =
        processor.GetMarkupAnnotationData(1).
        Where(annotation => annotation.Author.Contains("Cardle Anita L"));
    foreach (PdfMarkupAnnotationData markup in textMarkups)
    {
        //Get all text markup annotations from the retrieved list:
        PdfTextMarkupAnnotationData pdfTextMarkup =
         markup.AsTextMarkupAnnotation();
        if (pdfTextMarkup != null)
            //Change the annotation's markup type:
            pdfTextMarkup.MarkupType = PdfTextMarkupAnnotationType.Squiggly;
    }

    var annotations = processor.GetMarkupAnnotationData(1);
    foreach (PdfMarkupAnnotationData annotation in annotations)
    {
        //Get all text annotations:
        PdfTextAnnotationData textAnnotation = annotation.AsTextAnnotation();
        if (textAnnotation != null)

            //Change the annotation icon:
            textAnnotation.IconName = PdfTextAnnotationIconName.Note;
    }
}

Imports DevExpress.Pdf
Imports System
Imports System.Collections.Generic
'...

Private Shared Sub EditAnnotations(ByVal processor As PdfDocumentProcessor)
    'Retrieve annotations made by the specified author:
    Dim textMarkups = processor.GetMarkupAnnotationData(1).Where(Function(annotation) annotation.Author.Contains("Cardle Anita L"))
    For Each markup As PdfMarkupAnnotationData In textMarkups
        'Get all text markup annotations from the retrieved list:
        Dim pdfTextMarkup As PdfTextMarkupAnnotationData = markup.AsTextMarkupAnnotation()
        If pdfTextMarkup IsNot Nothing Then
            'Change the annotation's markup type:
            pdfTextMarkup.MarkupType = PdfTextMarkupAnnotationType.Squiggly
        End If
    Next markup

    Dim annotations = processor.GetMarkupAnnotationData(1)
    For Each annotation As PdfMarkupAnnotationData In annotations
        'Get all text annotations:
        Dim textAnnotation As PdfTextAnnotationData = annotation.AsTextAnnotation()
        If textAnnotation IsNot Nothing Then

            'Change the annotation icon:
            textAnnotation.IconName = PdfTextAnnotationIconName.Note
        End If
    Next annotation
End Sub

using DevExpress.Pdf;
using System.Linq;
//...
private static void DeleteAnnotations(PdfDocumentProcessor processor)
{
    for (int i = 0; i <= processor.Document.Pages.Count; i++)
    {
        //Remove Borman Aaron Lewis's markup annotations from a page.
        processor.DeleteMarkupAnnotations(processor.GetMarkupAnnotationData(i)
        .Where(annotation => annotation.Author.Contains("Borman Aaron Lewis")));
    }
}

Imports DevExpress.Pdf
Imports System.Linq
'...
Private Shared Sub DeleteAnnotations(ByVal processor As PdfDocumentProcessor)
    For i As Integer = 0 To processor.Document.Pages.Count
        'Remove Borman Aaron Lewis's markup annotations from a page.
        processor.DeleteMarkupAnnotations(processor.GetMarkupAnnotationData(i).Where(Function(annotation) annotation.Author.Contains("Borman Aaron Lewis")))
    Next i
End Sub