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Sometimes, we need to extract the OLE Objects that are embedded in a word document. With Spire.Doc, we can easily achieve this task with a few lines of code. This article explains how to extract the embedded PDF document and Excel workbook from a word document using Spire.Doc and C#.
Below is the screenshot of the word document:
Detail steps:
Step 1: Instantiate a Document object and load the word document.
Document doc = new Document();
doc.LoadFromFile("OleObject.docx");
Step 2: Traverse through the word document, find the Ole Objects, then get the Object type of each Ole Object to determine if the Ole Object is PDF document or Excel workbook and write the native data of the Ole object into a new PDF document or an Excel workbook.
//Traverse through all sections of the word document
foreach (Section sec in doc.Sections)
{
//Traverse through all Child Objects in the body of each section
foreach (DocumentObject obj in sec.Body.ChildObjects)
{
if (obj is Paragraph)
{
Paragraph par = obj as Paragraph;
//Traverse through all Child Objects in Paragraph
foreach (DocumentObject o in par.ChildObjects)
{
//Find the Ole Objects and Extract
if (o.DocumentObjectType == DocumentObjectType.OleObject)
{
DocOleObject Ole = o as DocOleObject;
string s = Ole.ObjectType;
//If s == "AcroExch.Document.11", means it’s a PDF document
if (s == "AcroExch.Document.11")
{
File.WriteAllBytes("Result.pdf", Ole.NativeData);
}
//If s == " Excel.Sheet.12", means it’s an Excel workbook
else if (s == "Excel.Sheet.12")
{
File.WriteAllBytes("Result.xlsx", Ole.NativeData);
}
}
}
}
}
}
Below is the screenshot of the extracted PDF file and Excel workbook after running the code:
Full codes:
using System.IO;
using Spire.Doc;
using Spire.Doc.Documents;
using Spire.Doc.Fields;
namespace Extract_OLEObjects_from_Word
{
class Program
{
static void Main(string[] args)
{
Document doc = new Document();
doc.LoadFromFile("OleObject.docx");
foreach (Section sec in doc.Sections)
{
foreach (DocumentObject obj in sec.Body.ChildObjects)
{
if (obj is Paragraph)
{
Paragraph par = obj as Paragraph;
foreach (DocumentObject o in par.ChildObjects)
{
if (o.DocumentObjectType == DocumentObjectType.OleObject)
{
DocOleObject Ole = o as DocOleObject;
string s = Ole.ObjectType;
if (s == "AcroExch.Document.11")
{
File.WriteAllBytes("Result.pdf", Ole.NativeData);
}
else if (s == "Excel.Sheet.12")
{
File.WriteAllBytes("Result.xlsx", Ole.NativeData);
}
}
}
}
}
}
}
}
}
Form fields are often used in documents like surveys, registration forms, or feedback forms to collect data from users. Extracting form field values allows you to gather and consolidate the submitted data for further analysis or processing. In this article, we will demonstrate how to extract form field values from PDF documents in C# and VB.NET using Spire.PDF for .NET.
Install Spire.PDF for .NET
To begin with, you need to add the DLL files included in the Spire.PDF for.NET package as references in your .NET project. The DLLs files can be either downloaded from this link or installed via NuGet.
PM> Install-Package Spire.PDF
Extract Form Field Values from PDF in C# and VB.NET
In a PDF document, you may encounter various types of form fields, such as textboxes, checkboxes, radio buttons, list boxes, and combo boxes (drop-down lists). Before extracting form field values, it is crucial to identify the specific type of each form field. Once identified, you can utilize corresponding properties tailored for each form field type to accurately extract their values. The detailed steps are as follows:
- Initialize an instance of the PdfDocument instance.
- Load a PDF document using PdfDocument.LoadFromFile() method.
- Initialize an instance of the StringBuilder class for storing the extract form field values.
- Get the form from the document using PdfDocument.Form property.
- Iterate through all form fields in the form.
- Determine the types of the form fields, then get the names and values of the form fields using the corresponding properties and append them to the StringBuilder instance.
- Write the content of the StringBuilder instance into a text file.
- C#
- VB.NET
using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Widget;
using System.IO;
using System.Text;
namespace ExtractFormFieldValues
{
internal class Program
{
static void Main(string[] args)
{
//Initialize an instance of the PdfDocument instance
PdfDocument doc = new PdfDocument();
//Load a PDF document
doc.LoadFromFile(@"Forms.pdf");
//Initialize an instance of the StringBuilder class
StringBuilder sb = new StringBuilder();
//Get the form from the document
PdfFormWidget formWidget = doc.Form as PdfFormWidget;
//Iterate through all fields in the form
for (int i = 0; i < formWidget.FieldsWidget.List.Count; i++)
{
PdfField field = formWidget.FieldsWidget.List[i] as PdfField;
//Get the name and value of textbox field
if (field is PdfTextBoxFieldWidget)
{
PdfTextBoxFieldWidget textBoxField = field as PdfTextBoxFieldWidget;
string name = textBoxField.Name;
string value = textBoxField.Text;
sb.Append("Textbox Name: " + name + "\r\n");
sb.Append("Textbox Value: " + value + "\r\n");
}
//Get the name, items and selected item of list box field
if (field is PdfListBoxWidgetFieldWidget)
{
PdfListBoxWidgetFieldWidget listBoxField = field as PdfListBoxWidgetFieldWidget;
string name = listBoxField.Name;
sb.Append("Listbox Name: " + name + "\r\n");
sb.Append("Listbox Items: \r\n");
PdfListWidgetItemCollection items = listBoxField.Values;
foreach (PdfListWidgetItem item in items)
{
sb.Append(item.Value + "\r\n");
}
string selectedValue = listBoxField.SelectedValue;
sb.Append("Listbox Selected Value: " + selectedValue + "\r\n");
}
//Get the name, items and selected item of combo box field
if (field is PdfComboBoxWidgetFieldWidget)
{
PdfComboBoxWidgetFieldWidget comBoxField = field as PdfComboBoxWidgetFieldWidget;
string name = comBoxField.Name;
sb.Append("Combobox Name: " + name + "\r\n");
sb.Append("Combobox Items: \r\n");
PdfListWidgetItemCollection items = comBoxField.Values;
foreach (PdfListWidgetItem item in items)
{
sb.Append(item.Value + "\r\n");
}
string selectedValue = comBoxField.SelectedValue;
sb.Append("Combobox Selected Value: " + selectedValue + "\r\n");
}
//Get the name and selected item of radio button field
if (field is PdfRadioButtonListFieldWidget)
{
PdfRadioButtonListFieldWidget radioBtnField = field as PdfRadioButtonListFieldWidget;
string name = radioBtnField.Name;
sb.Append("Radio Button Name: " + name + "\r\n");
string selectedValue = radioBtnField.SelectedValue;
sb.Append("Radio Button Selected Value: " + selectedValue + "\r\n");
}
//Get the name and status of checkbox field
if (field is PdfCheckBoxWidgetFieldWidget)
{
PdfCheckBoxWidgetFieldWidget checkBoxField = field as PdfCheckBoxWidgetFieldWidget;
string name = checkBoxField.Name;
sb.Append("Checkbox Name: " + name + "\r\n");
bool status = checkBoxField.Checked;
if (status)
{
sb.Append("Checkbox Status: Checked \r\n");
}
else
{
sb.Append("Checkbox Status: Unchecked \r\n");
}
}
sb.Append("\n");
}
//Write the content of the StringBuilder into a text file
File.WriteAllText("GetAllValues.txt", sb.ToString());
doc.Dispose();
}
}
}
Apply for a Temporary License
If you'd like to remove the evaluation message from the generated documents, or to get rid of the function limitations, please request a 30-day trial license for yourself.
An image watermark is usually a logo or sign that appears on the background of digital documents, indicating the copyright owner of the content. Watermarking your PDF document with an image can prevent your data from being reused or modified. This article demonstrates how to add an image watermark to PDF in C# and VB.NET using Spire.PDF for .NET.
Install Spire.PDF for .NET
To begin with, you need to add the DLL files included in the Spire.PDF for.NET package as references in your .NET project. The DLLs files can be either downloaded from this link or installed via NuGet.
- Package Manager
PM> Install-Package Spire.PDF
Add an Image Watermark to PDF
The following are the main steps to add an image watermark to a PDF document.
- Create a PdfDocument object, and load a sample PDF file using PdfDocument.LoadFromFile() method.
- Load an image file using Image.FromFile() method.
- Loop through the pages in the document, and get the specific page through PdfDocument.Pages[] property.
- Set the image as background/watermark image of the current page through PdfPageBase.BackgroundImage property. Set the image position and size through PdfPageBase.BackgroundRegion property.
- Save the document to a different PDF file using PdfDocument.SaveToFile() method.
- C#
- VB.NET
using Spire.Pdf;
using System.Drawing;
namespace AddImageWatermark
{
class Program
{
static void Main(string[] args)
{
//Create a PdfDocument object
PdfDocument document = new PdfDocument();
//Load a sample PDF document
document.LoadFromFile(@"C:\Users\Administrator\Desktop\sample.pdf");
//Load an image
Image image = Image.FromFile(@"C:\Users\Administrator\Desktop\logo.png");
//Get the image width and height
int imgWidth = image.Width;
int imgHeight = image.Height;
//Loop through the pages
for (int i = 0; i < document.Pages.Count; i++)
{
//Get the page width and height
float pageWidth = document.Pages[i].ActualSize.Width;
float pageHeight = document.Pages[i].ActualSize.Height;
//Set the background opacity
document.Pages[i].BackgroudOpacity = 0.3f;
//Set the background image of current page
document.Pages[i].BackgroundImage = image;
//Position the background image at the center of the page
Rectangle rect = new Rectangle((int)(pageWidth - imgWidth) / 2, (int)(pageHeight - imgHeight) / 2, imgWidth, imgHeight);
document.Pages[i].BackgroundRegion = rect;
}
//Save the document to file
document.SaveToFile("AddImageWatermark.pdf");
document.Close();
}
}
}
Imports Spire.Pdf
Imports System.Drawing
Namespace AddImageWatermark
Class Program
Shared Sub Main(ByVal args() As String)
'Create a PdfDocument object
Dim document As PdfDocument = New PdfDocument()
'Load a sample PDF document
document.LoadFromFile("C:\Users\Administrator\Desktop\sample.pdf")
'Load an image
Dim image As Image = Image.FromFile("C:\Users\Administrator\Desktop\logo.png")
'Get the image width and height
Dim imgWidth As Integer = image.Width
Dim imgHeight As Integer = image.Height
'Loop through the pages
Dim i As Integer
For i = 0 To document.Pages.Count- 1 Step i + 1
'Get the page width and height
Dim pageWidth As single = document.Pages(i).ActualSize.Width
Dim pageHeight As single = document.Pages(i).ActualSize.Height
'Set the background opacity
document.Pages(i).BackgroudOpacity = 0.3f
'Set the background image of current page
document.Pages(i).BackgroundImage = image
Dim rect As Rectangle = New Rectangle(CInt((pageWidth - imgWidth) / 2), CInt((pageHeight - imgHeight) / 2), imgWidth, imgHeight)
document.Pages(i).BackgroundRegion = rect
Next
'Save the document to file
document.SaveToFile("AddImageWatermark.pdf")
document.Close()
End Sub
End Class
End Namespace
Apply for a Temporary License
If you'd like to remove the evaluation message from the generated documents, or to get rid of the function limitations, please request a 30-day trial license for yourself.
