Working with OLE Objects
29 Nov 202424 minutes to read
OLE (Object Linking and Embedding) objects allow embedding and linking to documents and other objects. It allows the content of one program to be used in a Word document. The Objects can be inserted in the following two ways:
- Linked: The content is linked to the source file
- Embedded: The content is copied to the Word document and is not linked to the source file
You can create and manipulate the OLE Objects of both Linked and Embedded types in the Word document by using WOleObject instance.
Add OLE Objects in Word document
NOTE
Refer to the appropriate tabs in the code snippets section: C# [Cross-platform] for ASP.NET Core, Blazor, Xamarin, UWP, .NET MAUI, and WinUI; C# [Windows-specific] for WinForms and WPF; VB.NET [Windows-specific] for VB.NET applications.
The following code example explains how to add OLE objects to the document.
//Creates a new Word document
WordDocument document = new WordDocument();
//Adds new section to the document
IWSection section = document.AddSection();
//Adds new paragraph to the section
IWParagraph paragraph = section.AddParagraph();
//Opens the file to be embedded
FileStream fileStream = new FileStream("Book1.xlsx", FileMode.Open);
//Loads the picture instance with the image need to be displayed
WPicture picture = new WPicture(document);
FileStream imageStream = new FileStream(@"Image.png", FileMode.Open, FileAccess.ReadWrite);
picture.LoadImage(imageStream);
//Appends the OLE object to the paragraph
WOleObject oleObject = paragraph.AppendOleObject(fileStream, picture, OleObjectType.ExcelWorksheet);
//Saves the Word document to MemoryStream.
MemoryStream stream = new MemoryStream();
document.Save(stream, FormatType.Docx);
//Closes the Word document.
document.Close();//Creates a new Word document
WordDocument document = new WordDocument();
//Adds new section to the document
IWSection section = document.AddSection();
//Adds new paragraph to the section
IWParagraph paragraph = section.AddParagraph();
//Opens the file to be embedded
FileStream stream = new FileStream("Book1.xlsx", FileMode.Open);
//Loads the picture instance with the image need to be displayed
WPicture picture = new WPicture(document);
picture.LoadImage(Image.FromFile("Image.png"));
//Appends the OLE object to the paragraph
WOleObject oleObject = paragraph.AppendOleObject(stream, picture, OleObjectType.ExcelWorksheet);
//Saves the Word document
document.Save("Sample.docx", FormatType.Docx);
//Closes the document
document.Close();'Creates a new Word document
Dim document As New WordDocument()
'Adds new section to the document
Dim section As IWSection = document.AddSection()
'Adds new paragraph to the section
Dim paragraph As IWParagraph = section.AddParagraph()
'Opens the file to be embedded
Dim stream As New FileStream("Book1.xlsx", FileMode.Open)
'Loads the picture instance with the image need to be displayed
Dim picture As New WPicture(document)
picture.LoadImage(Image.FromFile("Image.png"))
'Appends the OLE object to the paragraph
Dim oleObject As WOleObject = paragraph.AppendOleObject(stream, picture, OleObjectType.ExcelWorksheet)
'Saves the Word document
document.Save("Sample.docx", FormatType.Docx)
'Closes the document
document.Close()You can download a complete working sample from GitHub.
Extract OLE Objects from Word document
The following code example explains how to extract OLE objects from the document and save as separate file.
using (FileStream inputStream = new FileStream(@"Template.docx", FileMode.Open, FileAccess.Read))
{
using (WordDocument document = new WordDocument(inputStream, FormatType.Docx))
{
// Extract the OLE object from the word document
ExtractOLEObject(document);
}
}
private static void ExtractOLEObject(WordDocument document)
{
WOleObject oleObject = null;
int oleIndex = -1;
// Retrieving embedded object.
foreach (WSection section in document.Sections)
{
foreach (WParagraph paragraph in section.Paragraphs)
{
foreach (Entity entity in paragraph.ChildEntities)
{
//Checks for oleObject
if (entity.EntityType == EntityType.OleObject)
{
//Gets OleObject
oleObject = entity as WOleObject;
//Gets index of OleObject
oleIndex = paragraph.ChildEntities.IndexOf(oleObject);
//Gets ole type
string oleTypeStr = oleObject.ObjectType;
// Checks for Excel type so that file can be saved with proper extension.
if (oleTypeStr.Contains("Excel 2003 Worksheet") || oleTypeStr.StartsWith("Excel.Sheet.8") || (oleTypeStr.Contains("Excel Worksheet") || oleTypeStr.StartsWith("Excel.Sheet.12")))
{
if ((oleTypeStr.Contains("Excel Worksheet") || oleTypeStr.StartsWith("Excel.Sheet.12")))
{
FileStream fstream = new FileStream("Workbook" + oleObject.OleStorageName + ".xlsx", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
else
{
FileStream fstream = new FileStream("Workbook" + oleObject.OleStorageName + ".xls", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
}
//Checks for Word document embedded object and save them
if (oleTypeStr.Contains("Word.Document"))
{
if (oleTypeStr.Contains("Word.Document.12"))
{
FileStream fstream = new FileStream("Sample" + oleObject.OleStorageName + ".docx", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
else if (oleTypeStr.Contains("Word.Document.8"))
{
FileStream fstream = new FileStream("Sample" + oleObject.OleStorageName + ".doc", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
}
//Checks for PDF embedded object and save them
if (oleTypeStr.Contains("Acrobat Document") || oleTypeStr.StartsWith("AcroExch.Document.7") || (oleTypeStr.Contains("AcroExch.Document.11") || oleTypeStr.StartsWith("AcroExch.Document.DC")))
{
FileStream fstream = new FileStream("Sample" + oleObject.OleStorageName + ".pdf", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
}
}
}
}
}//Opens an existing document
using (WordDocument document = new WordDocument("Template.docx"))
{
// Extract the OLE object from the word document
ExtractOLEObject(document);
}
private static void ExtractOLEObject(WordDocument document)
{
WOleObject oleObject = null;
int oleIndex = -1;
// Retrieving embedded object.
foreach (WSection section in document.Sections)
{
foreach (WParagraph paragraph in section.Paragraphs)
{
foreach (Entity entity in paragraph.ChildEntities)
{
//Checks for oleObject
if (entity.EntityType == EntityType.OleObject)
{
//Gets OleObject
oleObject = entity as WOleObject;
//Gets index of OleObject
oleIndex = paragraph.ChildEntities.IndexOf(oleObject);
//Gets ole type
string oleTypeStr = oleObject.ObjectType;
// Checks for Excel type so that file can be saved with proper extension.
if (oleTypeStr.Contains("Excel 2003 Worksheet") || oleTypeStr.StartsWith("Excel.Sheet.8") || (oleTypeStr.Contains("Excel Worksheet") || oleTypeStr.StartsWith("Excel.Sheet.12")))
{
if ((oleTypeStr.Contains("Excel Worksheet") || oleTypeStr.StartsWith("Excel.Sheet.12")))
{
FileStream fstream = new FileStream("Workbook" + oleObject.OleStorageName + ".xlsx", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
else
{
FileStream fstream = new FileStream("Workbook" + oleObject.OleStorageName + ".xls", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
}
//Checks for Word document embedded object and save them
if (oleTypeStr.Contains("Word.Document"))
{
if (oleTypeStr.Contains("Word.Document.12"))
{
FileStream fstream = new FileStream("Sample" + oleObject.OleStorageName + ".docx", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
else if (oleTypeStr.Contains("Word.Document.8"))
{
FileStream fstream = new FileStream("Sample" + oleObject.OleStorageName + ".doc", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
}
//Checks for PDF embedded object and save them
if (oleTypeStr.Contains("Acrobat Document") || oleTypeStr.StartsWith("AcroExch.Document.7") || (oleTypeStr.Contains("AcroExch.Document.11") || oleTypeStr.StartsWith("AcroExch.Document.DC")))
{
FileStream fstream = new FileStream("Sample" + oleObject.OleStorageName + ".pdf", FileMode.Create);
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length);
fstream.Flush();
fstream.Close();
break;
}
}
}
}
}
}'Opens an existing document
Using document As WordDocument = New WordDocument(inputFileName)
'Extract the OLE object from the word document
ExtractOLEObject(document)
End Using
Private Shared Sub ExtractOLEObject(ByVal document As WordDocument)
Dim oleObject As WOleObject = Nothing
Dim oleIndex As Integer = -1
' Retrieving embedded object.
For Each section As WSection In document.Sections
For Each paragraph As WParagraph In section.Paragraphs
For Each entity As Entity In paragraph.ChildEntities
'Checks for oleObject
If entity.EntityType Is EntityType.OleObject Then
'Gets OleObject
oleObject = TryCast(entity, WOleObject)
'Gets index of OleObject
oleIndex = paragraph.ChildEntities.IndexOf(oleObject)
'Gets ole type
Dim oleTypeStr As String = oleObject.ObjectType
' Checks for Excel type so that file can be saved with proper extension.
If oleTypeStr.Contains("Excel 2003 Worksheet") OrElse oleTypeStr.StartsWith("Excel.Sheet.8") OrElse oleTypeStr.Contains("Excel Worksheet") OrElse oleTypeStr.StartsWith("Excel.Sheet.12") Then
If oleTypeStr.Contains("Excel Worksheet") OrElse oleTypeStr.StartsWith("Excel.Sheet.12") Then
Dim fstream As FileStream = New FileStream("Workbook" & oleObject.OleStorageName & ".xlsx", FileMode.Create)
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length)
fstream.Flush()
fstream.Close()
Exit For
Else
Dim fstream As FileStream = New FileStream("Workbook" & oleObject.OleStorageName & ".xls", FileMode.Create)
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length)
fstream.Flush()
fstream.Close()
Exit For
End If
End If
'Checks for Word document embedded object and save them
If oleTypeStr.Contains("Word.Document") Then
If oleTypeStr.Contains("Word.Document.12") Then
Dim fstream As FileStream = New FileStream("Sample" & oleObject.OleStorageName & ".docx", FileMode.Create)
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length)
fstream.Flush()
fstream.Close()
Exit For
ElseIf oleTypeStr.Contains("Word.Document.8") Then
Dim fstream As FileStream = New FileStream("Sample" & oleObject.OleStorageName & ".doc", FileMode.Create)
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length)
fstream.Flush()
fstream.Close()
Exit For
End If
End If
'Checks for PDF embedded object and save them
If oleTypeStr.Contains("Acrobat Document") OrElse oleTypeStr.StartsWith("AcroExch.Document.7") OrElse oleTypeStr.Contains("AcroExch.Document.11") OrElse oleTypeStr.StartsWith("AcroExch.Document.DC") Then
Dim fstream As FileStream = New FileStream("Sample" & oleObject.OleStorageName & ".pdf", FileMode.Create)
fstream.Write(oleObject.NativeData, 0, oleObject.NativeData.Length)
fstream.Flush()
fstream.Close()
Exit For
End If
End If
Next
Next
Next
End SubYou can download a complete working sample from GitHub.
Remove OLE Objects from Word document
The following code example explains how to remove OLE objects from the document.
FileStream inputStream = new FileStream(@"Input.docx", FileMode.Open, FileAccess.Read);
WordDocument document = new WordDocument(inputStream, FormatType.Automatic);
inputStream.Dispose();
//Remove OLE object from the document
RemoveOLEObject(document);
//Saves the Word document to MemoryStream.
MemoryStream stream = new MemoryStream();
document.Save(stream, FormatType.Docx);
//Closes the Word document.
document.Close();
private static void RemoveOLEObject(WordDocument document)
{
bool isFieldStart = false;
// Retrieving embedded object.
foreach (WSection section in document.Sections)
{
foreach (WParagraph paragraph in section.Paragraphs)
{
for (int i = 0; i < paragraph.ChildEntities.Count; i++)
{
Entity entity = paragraph.ChildEntities[i];
//Checks for oleObject
if (entity.EntityType == EntityType.OleObject)
{
paragraph.ChildEntities.Remove(entity);
isFieldStart = true;
i--;
}
else if (isFieldStart && entity.EntityType == EntityType.FieldMark
&& (entity as WFieldMark).Type == FieldMarkType.FieldEnd)
{
paragraph.ChildEntities.Remove(entity);
isFieldStart = false;
i--;
}
else if (isFieldStart)
{
paragraph.ChildEntities.Remove(entity);
i--;
}
}
}
}
}//Opens the source document
WordDocument document = new WordDocument(@"Template.docx");
//Remove OLE object from the document
RemoveOLEObject(document);
//Saves the Word document
document.Save("Output.docx", FormatType.Docx);
//Closes the document
document.Close();
private static void RemoveOLEObject(WordDocument document)
{
bool isFieldStart = false;
// Retrieving embedded object.
foreach (WSection section in document.Sections)
{
foreach (WParagraph paragraph in section.Paragraphs)
{
for (int i = 0; i < paragraph.ChildEntities.Count; i++)
{
Entity entity = paragraph.ChildEntities[i];
//Checks for oleObject
if (entity.EntityType == EntityType.OleObject)
{
paragraph.ChildEntities.Remove(entity);
isFieldStart = true;
i--;
}
else if (isFieldStart && entity.EntityType == EntityType.FieldMark
&& (entity as WFieldMark).Type == FieldMarkType.FieldEnd)
{
paragraph.ChildEntities.Remove(entity);
isFieldStart = false;
i--;
}
else if (isFieldStart)
{
paragraph.ChildEntities.Remove(entity);
i--;
}
}
}
}
}'Opens the source document
Dim document As WordDocument = New WordDocument("Template.docx")
'Remove OLE object from the document
RemoveOLEObject(document)
'Saves the Word document
document.Save("Output.docx", FormatType.Docx)
'Closes the document
document.Close()
Private Shared Sub RemoveOLEObject(ByVal document As WordDocument)
Dim isFieldStart As Boolean = False
'Retrieving embedded object.
For Each section As WSection In document.Sections
For Each paragraph As WParagraph In section.Paragraphs
For i As Integer = 0 To paragraph.ChildEntities.Count - 1
Dim entity As Entity = paragraph.ChildEntities(i)
'Checks for oleObject
If entity.EntityType Is EntityType.OleObject Then
paragraph.ChildEntities.Remove(entity)
isFieldStart = True
i -= 1
ElseIf isFieldStart AndAlso entity.EntityType Is EntityType.FieldMark AndAlso TryCast(entity, WFieldMark).Type Is FieldMarkType.FieldEnd Then
paragraph.ChildEntities.Remove(entity)
isFieldStart = False
i -= 1
ElseIf isFieldStart Then
paragraph.ChildEntities.Remove(entity)
i -= 1
End If
Next
Next
Next
End SubYou can download a complete working sample from GitHub.
Online Demo
- Explore how to insert an OLE Object into the Word document using the .NET Word Library (DocIO) in a live demo here.