PM> Install-Package Spire.Doc

using Spire.Doc;
    
    namespace BuiltinDocumentProperties
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a Document instance
                Document document = new Document();
                //Load a Word document
                document.LoadFromFile("Sample.docx");
    
                //Add built-in document properties to the document
                BuiltinDocumentProperties standardProperties = document.BuiltinDocumentProperties;
                standardProperties.Title = "Add Document Properties";
                standardProperties.Subject = "C# Example";
                standardProperties.Author = "James";
                standardProperties.Company = "Eiceblue";
                standardProperties.Manager = "Michael";
                standardProperties.Category = "Document Manipulation";
                standardProperties.Keywords = "C#, Word, Document Properties";
                standardProperties.Comments = "This article shows how to add document properties";
    
                //Save the result document
                document.SaveToFile("StandardDocumentProperties.docx", FileFormat.Docx2013);
            }
        }
    }

Imports Spire.Doc
    
    Namespace BuiltinDocumentProperties
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a Document instance
                Dim document As Document = New Document()
                'Load a Word document
                document.LoadFromFile("Sample.docx")
    
                'Add built-in document properties to the document
                Dim standardProperties As BuiltinDocumentProperties = document.BuiltinDocumentProperties
                standardProperties.Title = "Add Document Properties"
                standardProperties.Subject = "C# Example"
                standardProperties.Author = "James"
                standardProperties.Company = "Eiceblue"
                standardProperties.Manager = "Michael"
                standardProperties.Category = "Document Manipulation"
                standardProperties.Keywords = "C#, Word, Document Properties"
                standardProperties.Comments = "This article shows how to add document properties"
    
                'Save the result document
                document.SaveToFile("StandardDocumentProperties.docx", FileFormat.Docx2013)
            End Sub
        End Class
    End Namespace

using Spire.Doc;
    using System;
    
    namespace CustomDocumentProperties
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a Document instance
                Document document = new Document();
                //Load a Word document
                document.LoadFromFile("Sample.docx");
    
                //Add custom document properties to the document
                CustomDocumentProperties customProperties = document.CustomDocumentProperties;
                customProperties.Add("Document ID", 1);
                customProperties.Add("Authorized", true);
                customProperties.Add("Authorized By", "John Smith");
                customProperties.Add("Authorized Date", DateTime.Today);
    
                //Save the result document
                document.SaveToFile("CustomDocumentProperties.docx", FileFormat.Docx2013);
            }
        }
    }

Imports Spire.Doc
    
    Namespace CustomDocumentProperties
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a Document instance
                Dim document As Document = New Document()
                'Load a Word document
                document.LoadFromFile("Sample.docx")
    
                'Add custom document properties to the document
                Dim customProperties As CustomDocumentProperties = document.CustomDocumentProperties
                customProperties.Add("Document ID", 1)
                customProperties.Add("Authorized", True)
                customProperties.Add("Authorized By", "John Smith")
                customProperties.Add("Authorized Date", Date.Today)
    
                'Save the result document
                document.SaveToFile("CustomDocumentProperties.docx", FileFormat.Docx2013)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.Doc

using Spire.Doc;
    
    namespace BuiltinDocumentProperties
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a Document instance
                Document document = new Document();
                //Load a Word document
                document.LoadFromFile("Sample.docx");
    
                //Add built-in document properties to the document
                BuiltinDocumentProperties standardProperties = document.BuiltinDocumentProperties;
                standardProperties.Title = "Add Document Properties";
                standardProperties.Subject = "C# Example";
                standardProperties.Author = "James";
                standardProperties.Company = "Eiceblue";
                standardProperties.Manager = "Michael";
                standardProperties.Category = "Document Manipulation";
                standardProperties.Keywords = "C#, Word, Document Properties";
                standardProperties.Comments = "This article shows how to add document properties";
    
                //Save the result document
                document.SaveToFile("StandardDocumentProperties.docx", FileFormat.Docx2013);
            }
        }
    }

Imports Spire.Doc
    
    Namespace BuiltinDocumentProperties
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a Document instance
                Dim document As Document = New Document()
                'Load a Word document
                document.LoadFromFile("Sample.docx")
    
                'Add built-in document properties to the document
                Dim standardProperties As BuiltinDocumentProperties = document.BuiltinDocumentProperties
                standardProperties.Title = "Add Document Properties"
                standardProperties.Subject = "C# Example"
                standardProperties.Author = "James"
                standardProperties.Company = "Eiceblue"
                standardProperties.Manager = "Michael"
                standardProperties.Category = "Document Manipulation"
                standardProperties.Keywords = "C#, Word, Document Properties"
                standardProperties.Comments = "This article shows how to add document properties"
    
                'Save the result document
                document.SaveToFile("StandardDocumentProperties.docx", FileFormat.Docx2013)
            End Sub
        End Class
    End Namespace

using Spire.Doc;
    using System;
    
    namespace CustomDocumentProperties
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a Document instance
                Document document = new Document();
                //Load a Word document
                document.LoadFromFile("Sample.docx");
    
                //Add custom document properties to the document
                CustomDocumentProperties customProperties = document.CustomDocumentProperties;
                customProperties.Add("Document ID", 1);
                customProperties.Add("Authorized", true);
                customProperties.Add("Authorized By", "John Smith");
                customProperties.Add("Authorized Date", DateTime.Today);
    
                //Save the result document
                document.SaveToFile("CustomDocumentProperties.docx", FileFormat.Docx2013);
            }
        }
    }

Imports Spire.Doc
    
    Namespace CustomDocumentProperties
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a Document instance
                Dim document As Document = New Document()
                'Load a Word document
                document.LoadFromFile("Sample.docx")
    
                'Add custom document properties to the document
                Dim customProperties As CustomDocumentProperties = document.CustomDocumentProperties
                customProperties.Add("Document ID", 1)
                customProperties.Add("Authorized", True)
                customProperties.Add("Authorized By", "John Smith")
                customProperties.Add("Authorized Date", Date.Today)
    
                'Save the result document
                document.SaveToFile("CustomDocumentProperties.docx", FileFormat.Docx2013)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.Doc

using Spire.Doc;
    
    namespace BuiltinDocumentProperties
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a Document instance
                Document document = new Document();
                //Load a Word document
                document.LoadFromFile("Sample.docx");
    
                //Add built-in document properties to the document
                BuiltinDocumentProperties standardProperties = document.BuiltinDocumentProperties;
                standardProperties.Title = "Add Document Properties";
                standardProperties.Subject = "C# Example";
                standardProperties.Author = "James";
                standardProperties.Company = "Eiceblue";
                standardProperties.Manager = "Michael";
                standardProperties.Category = "Document Manipulation";
                standardProperties.Keywords = "C#, Word, Document Properties";
                standardProperties.Comments = "This article shows how to add document properties";
    
                //Save the result document
                document.SaveToFile("StandardDocumentProperties.docx", FileFormat.Docx2013);
            }
        }
    }

Imports Spire.Doc
    
    Namespace BuiltinDocumentProperties
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a Document instance
                Dim document As Document = New Document()
                'Load a Word document
                document.LoadFromFile("Sample.docx")
    
                'Add built-in document properties to the document
                Dim standardProperties As BuiltinDocumentProperties = document.BuiltinDocumentProperties
                standardProperties.Title = "Add Document Properties"
                standardProperties.Subject = "C# Example"
                standardProperties.Author = "James"
                standardProperties.Company = "Eiceblue"
                standardProperties.Manager = "Michael"
                standardProperties.Category = "Document Manipulation"
                standardProperties.Keywords = "C#, Word, Document Properties"
                standardProperties.Comments = "This article shows how to add document properties"
    
                'Save the result document
                document.SaveToFile("StandardDocumentProperties.docx", FileFormat.Docx2013)
            End Sub
        End Class
    End Namespace

using Spire.Doc;
    using System;
    
    namespace CustomDocumentProperties
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a Document instance
                Document document = new Document();
                //Load a Word document
                document.LoadFromFile("Sample.docx");
    
                //Add custom document properties to the document
                CustomDocumentProperties customProperties = document.CustomDocumentProperties;
                customProperties.Add("Document ID", 1);
                customProperties.Add("Authorized", true);
                customProperties.Add("Authorized By", "John Smith");
                customProperties.Add("Authorized Date", DateTime.Today);
    
                //Save the result document
                document.SaveToFile("CustomDocumentProperties.docx", FileFormat.Docx2013);
            }
        }
    }

Imports Spire.Doc
    
    Namespace CustomDocumentProperties
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a Document instance
                Dim document As Document = New Document()
                'Load a Word document
                document.LoadFromFile("Sample.docx")
    
                'Add custom document properties to the document
                Dim customProperties As CustomDocumentProperties = document.CustomDocumentProperties
                customProperties.Add("Document ID", 1)
                customProperties.Add("Authorized", True)
                customProperties.Add("Authorized By", "John Smith")
                customProperties.Add("Authorized Date", Date.Today)
    
                'Save the result document
                document.SaveToFile("CustomDocumentProperties.docx", FileFormat.Docx2013)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.Doc

using Spire.Doc;
    
    namespace BuiltinDocumentProperties
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a Document instance
                Document document = new Document();
                //Load a Word document
                document.LoadFromFile("Sample.docx");
    
                //Add built-in document properties to the document
                BuiltinDocumentProperties standardProperties = document.BuiltinDocumentProperties;
                standardProperties.Title = "Add Document Properties";
                standardProperties.Subject = "C# Example";
                standardProperties.Author = "James";
                standardProperties.Company = "Eiceblue";
                standardProperties.Manager = "Michael";
                standardProperties.Category = "Document Manipulation";
                standardProperties.Keywords = "C#, Word, Document Properties";
                standardProperties.Comments = "This article shows how to add document properties";
    
                //Save the result document
                document.SaveToFile("StandardDocumentProperties.docx", FileFormat.Docx2013);
            }
        }
    }

Imports Spire.Doc
    
    Namespace BuiltinDocumentProperties
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a Document instance
                Dim document As Document = New Document()
                'Load a Word document
                document.LoadFromFile("Sample.docx")
    
                'Add built-in document properties to the document
                Dim standardProperties As BuiltinDocumentProperties = document.BuiltinDocumentProperties
                standardProperties.Title = "Add Document Properties"
                standardProperties.Subject = "C# Example"
                standardProperties.Author = "James"
                standardProperties.Company = "Eiceblue"
                standardProperties.Manager = "Michael"
                standardProperties.Category = "Document Manipulation"
                standardProperties.Keywords = "C#, Word, Document Properties"
                standardProperties.Comments = "This article shows how to add document properties"
    
                'Save the result document
                document.SaveToFile("StandardDocumentProperties.docx", FileFormat.Docx2013)
            End Sub
        End Class
    End Namespace

using Spire.Doc;
    using System;
    
    namespace CustomDocumentProperties
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a Document instance
                Document document = new Document();
                //Load a Word document
                document.LoadFromFile("Sample.docx");
    
                //Add custom document properties to the document
                CustomDocumentProperties customProperties = document.CustomDocumentProperties;
                customProperties.Add("Document ID", 1);
                customProperties.Add("Authorized", true);
                customProperties.Add("Authorized By", "John Smith");
                customProperties.Add("Authorized Date", DateTime.Today);
    
                //Save the result document
                document.SaveToFile("CustomDocumentProperties.docx", FileFormat.Docx2013);
            }
        }
    }

Imports Spire.Doc
    
    Namespace CustomDocumentProperties
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a Document instance
                Dim document As Document = New Document()
                'Load a Word document
                document.LoadFromFile("Sample.docx")
    
                'Add custom document properties to the document
                Dim customProperties As CustomDocumentProperties = document.CustomDocumentProperties
                customProperties.Add("Document ID", 1)
                customProperties.Add("Authorized", True)
                customProperties.Add("Authorized By", "John Smith")
                customProperties.Add("Authorized Date", Date.Today)
    
                'Save the result document
                document.SaveToFile("CustomDocumentProperties.docx", FileFormat.Docx2013)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Texts;
    using System.Collections.Generic;
    using System.Drawing;
    
    namespace HighlightTextInPdf
    {
        internal class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
                //Load a PDF file
                pdf.LoadFromFile("Sample.pdf");
    
                //Creare a PdfTextFindOptions instance
                PdfTextFindOptions findOptions = new PdfTextFindOptions();
                //Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord;
    
                //Loop through the pages in the PDF file
                foreach (PdfPageBase page in pdf.Pages)
                {
                    //Create a PdfTextFinder instance
                    PdfTextFinder finder = new PdfTextFinder(page);
                    //Set the text finding option
                    finder.Options = findOptions;
                    //Find a specific text
                    List<PdfTextFragment> results = finder.Find("Video");
                    //Highlight all occurrences of the specific text
                    foreach (PdfTextFragment text in results)
                    {
                        text.HighLight(Color.Green);
                    }
                }
    
                //Save the result file
                pdf.SaveToFile("HighlightText.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Texts
    Imports System.Collections.Generic
    Imports System.Drawing
    
    Namespace HighlightTextInPdf
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument()
                'Load a PDF file
                pdf.LoadFromFile("Sample.pdf")
    
                'Creare a PdfTextFindOptions instance
                Dim findOptions As PdfTextFindOptions = New PdfTextFindOptions()
                'Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord
    
                'Loop through the pages in the PDF file
                For Each page As PdfPageBase In pdf.Pages
                    'Create a PdfTextFinder instance
                    Dim finder As PdfTextFinder = New PdfTextFinder(page)
                    'Set the text finding option
                    finder.Options = findOptions
                    'Find a specific text
                    Dim results As List(Of PdfTextFragment) = finder.Find("Video")
                    'Highlight all occurrences of the specific text
                    For Each text As PdfTextFragment In results
                        text.HighLight(Color.Green)
                    Next
                Next
    
                'Save the result file
                pdf.SaveToFile("HighlightText.pdf")
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Texts;
    using System.Collections.Generic;
    using System.Drawing;
    
    namespace HighlightTextInPdf
    {
        internal class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
                //Load a PDF file
                pdf.LoadFromFile("Sample.pdf");
    
                //Creare a PdfTextFindOptions instance
                PdfTextFindOptions findOptions = new PdfTextFindOptions();
                //Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord;
    
                //Loop through the pages in the PDF file
                foreach (PdfPageBase page in pdf.Pages)
                {
                    //Create a PdfTextFinder instance
                    PdfTextFinder finder = new PdfTextFinder(page);
                    //Set the text finding option
                    finder.Options = findOptions;
                    //Find a specific text
                    List<PdfTextFragment> results = finder.Find("Video");
                    //Highlight all occurrences of the specific text
                    foreach (PdfTextFragment text in results)
                    {
                        text.HighLight(Color.Green);
                    }
                }
    
                //Save the result file
                pdf.SaveToFile("HighlightText.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Texts
    Imports System.Collections.Generic
    Imports System.Drawing
    
    Namespace HighlightTextInPdf
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument()
                'Load a PDF file
                pdf.LoadFromFile("Sample.pdf")
    
                'Creare a PdfTextFindOptions instance
                Dim findOptions As PdfTextFindOptions = New PdfTextFindOptions()
                'Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord
    
                'Loop through the pages in the PDF file
                For Each page As PdfPageBase In pdf.Pages
                    'Create a PdfTextFinder instance
                    Dim finder As PdfTextFinder = New PdfTextFinder(page)
                    'Set the text finding option
                    finder.Options = findOptions
                    'Find a specific text
                    Dim results As List(Of PdfTextFragment) = finder.Find("Video")
                    'Highlight all occurrences of the specific text
                    For Each text As PdfTextFragment In results
                        text.HighLight(Color.Green)
                    Next
                Next
    
                'Save the result file
                pdf.SaveToFile("HighlightText.pdf")
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Texts;
    using System.Collections.Generic;
    using System.Drawing;
    
    namespace HighlightTextInPdf
    {
        internal class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
                //Load a PDF file
                pdf.LoadFromFile("Sample.pdf");
    
                //Creare a PdfTextFindOptions instance
                PdfTextFindOptions findOptions = new PdfTextFindOptions();
                //Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord;
    
                //Loop through the pages in the PDF file
                foreach (PdfPageBase page in pdf.Pages)
                {
                    //Create a PdfTextFinder instance
                    PdfTextFinder finder = new PdfTextFinder(page);
                    //Set the text finding option
                    finder.Options = findOptions;
                    //Find a specific text
                    List<PdfTextFragment> results = finder.Find("Video");
                    //Highlight all occurrences of the specific text
                    foreach (PdfTextFragment text in results)
                    {
                        text.HighLight(Color.Green);
                    }
                }
    
                //Save the result file
                pdf.SaveToFile("HighlightText.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Texts
    Imports System.Collections.Generic
    Imports System.Drawing
    
    Namespace HighlightTextInPdf
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument()
                'Load a PDF file
                pdf.LoadFromFile("Sample.pdf")
    
                'Creare a PdfTextFindOptions instance
                Dim findOptions As PdfTextFindOptions = New PdfTextFindOptions()
                'Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord
    
                'Loop through the pages in the PDF file
                For Each page As PdfPageBase In pdf.Pages
                    'Create a PdfTextFinder instance
                    Dim finder As PdfTextFinder = New PdfTextFinder(page)
                    'Set the text finding option
                    finder.Options = findOptions
                    'Find a specific text
                    Dim results As List(Of PdfTextFragment) = finder.Find("Video")
                    'Highlight all occurrences of the specific text
                    For Each text As PdfTextFragment In results
                        text.HighLight(Color.Green)
                    Next
                Next
    
                'Save the result file
                pdf.SaveToFile("HighlightText.pdf")
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Texts;
    using System.Collections.Generic;
    using System.Drawing;
    
    namespace HighlightTextInPdf
    {
        internal class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
                //Load a PDF file
                pdf.LoadFromFile("Sample.pdf");
    
                //Creare a PdfTextFindOptions instance
                PdfTextFindOptions findOptions = new PdfTextFindOptions();
                //Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord;
    
                //Loop through the pages in the PDF file
                foreach (PdfPageBase page in pdf.Pages)
                {
                    //Create a PdfTextFinder instance
                    PdfTextFinder finder = new PdfTextFinder(page);
                    //Set the text finding option
                    finder.Options = findOptions;
                    //Find a specific text
                    List<PdfTextFragment> results = finder.Find("Video");
                    //Highlight all occurrences of the specific text
                    foreach (PdfTextFragment text in results)
                    {
                        text.HighLight(Color.Green);
                    }
                }
    
                //Save the result file
                pdf.SaveToFile("HighlightText.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Texts
    Imports System.Collections.Generic
    Imports System.Drawing
    
    Namespace HighlightTextInPdf
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument()
                'Load a PDF file
                pdf.LoadFromFile("Sample.pdf")
    
                'Creare a PdfTextFindOptions instance
                Dim findOptions As PdfTextFindOptions = New PdfTextFindOptions()
                'Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord
    
                'Loop through the pages in the PDF file
                For Each page As PdfPageBase In pdf.Pages
                    'Create a PdfTextFinder instance
                    Dim finder As PdfTextFinder = New PdfTextFinder(page)
                    'Set the text finding option
                    finder.Options = findOptions
                    'Find a specific text
                    Dim results As List(Of PdfTextFragment) = finder.Find("Video")
                    'Highlight all occurrences of the specific text
                    For Each text As PdfTextFragment In results
                        text.HighLight(Color.Green)
                    Next
                Next
    
                'Save the result file
                pdf.SaveToFile("HighlightText.pdf")
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Texts;
    using System.Collections.Generic;
    using System.Drawing;
    
    namespace HighlightTextInPdf
    {
        internal class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
                //Load a PDF file
                pdf.LoadFromFile("Sample.pdf");
    
                //Creare a PdfTextFindOptions instance
                PdfTextFindOptions findOptions = new PdfTextFindOptions();
                //Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord;
    
                //Loop through the pages in the PDF file
                foreach (PdfPageBase page in pdf.Pages)
                {
                    //Create a PdfTextFinder instance
                    PdfTextFinder finder = new PdfTextFinder(page);
                    //Set the text finding option
                    finder.Options = findOptions;
                    //Find a specific text
                    List<PdfTextFragment> results = finder.Find("Video");
                    //Highlight all occurrences of the specific text
                    foreach (PdfTextFragment text in results)
                    {
                        text.HighLight(Color.Green);
                    }
                }
    
                //Save the result file
                pdf.SaveToFile("HighlightText.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Texts
    Imports System.Collections.Generic
    Imports System.Drawing
    
    Namespace HighlightTextInPdf
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument()
                'Load a PDF file
                pdf.LoadFromFile("Sample.pdf")
    
                'Creare a PdfTextFindOptions instance
                Dim findOptions As PdfTextFindOptions = New PdfTextFindOptions()
                'Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord
    
                'Loop through the pages in the PDF file
                For Each page As PdfPageBase In pdf.Pages
                    'Create a PdfTextFinder instance
                    Dim finder As PdfTextFinder = New PdfTextFinder(page)
                    'Set the text finding option
                    finder.Options = findOptions
                    'Find a specific text
                    Dim results As List(Of PdfTextFragment) = finder.Find("Video")
                    'Highlight all occurrences of the specific text
                    For Each text As PdfTextFragment In results
                        text.HighLight(Color.Green)
                    Next
                Next
    
                'Save the result file
                pdf.SaveToFile("HighlightText.pdf")
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Texts;
    using System.Collections.Generic;
    using System.Drawing;
    
    namespace HighlightTextInPdf
    {
        internal class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
                //Load a PDF file
                pdf.LoadFromFile("Sample.pdf");
    
                //Creare a PdfTextFindOptions instance
                PdfTextFindOptions findOptions = new PdfTextFindOptions();
                //Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord;
    
                //Loop through the pages in the PDF file
                foreach (PdfPageBase page in pdf.Pages)
                {
                    //Create a PdfTextFinder instance
                    PdfTextFinder finder = new PdfTextFinder(page);
                    //Set the text finding option
                    finder.Options = findOptions;
                    //Find a specific text
                    List<PdfTextFragment> results = finder.Find("Video");
                    //Highlight all occurrences of the specific text
                    foreach (PdfTextFragment text in results)
                    {
                        text.HighLight(Color.Green);
                    }
                }
    
                //Save the result file
                pdf.SaveToFile("HighlightText.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Texts
    Imports System.Collections.Generic
    Imports System.Drawing
    
    Namespace HighlightTextInPdf
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument()
                'Load a PDF file
                pdf.LoadFromFile("Sample.pdf")
    
                'Creare a PdfTextFindOptions instance
                Dim findOptions As PdfTextFindOptions = New PdfTextFindOptions()
                'Specify the text finding parameter
                findOptions.Parameter = TextFindParameter.WholeWord
    
                'Loop through the pages in the PDF file
                For Each page As PdfPageBase In pdf.Pages
                    'Create a PdfTextFinder instance
                    Dim finder As PdfTextFinder = New PdfTextFinder(page)
                    'Set the text finding option
                    finder.Options = findOptions
                    'Find a specific text
                    Dim results As List(Of PdfTextFragment) = finder.Find("Video")
                    'Highlight all occurrences of the specific text
                    For Each text As PdfTextFragment In results
                        text.HighLight(Color.Green)
                    Next
                Next
    
                'Save the result file
                pdf.SaveToFile("HighlightText.pdf")
            End Sub
        End Class
    End Namespace