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The sample demonstrates how to Set PDF Text Format for Silverlight via Spire.PDF.
The sample demonstrates how to Create Table in Word for Silverlight via Spire.Doc.
The sample demonstrates how to Edit Excel in Silverlight via Spire.XLS.
Effortlessly Automate PDF Text Extraction Using C# .NET: A Complete Guide
2022-07-29 06:33:00 Written by Koohji
Manually extracting text from PDF files can be tedious, error-prone, and inefficient—especially when working with large volumes of documents or complex layouts. PDFs store content based on coordinates rather than linear text flow, making it difficult to retrieve structured or readable text without specialized tools.
For developers working in C# .NET, automating PDF text extraction is essential for streamlining workflows such as document processing, content indexing, data migration, and digital archiving.
This comprehensive guide shows you how to read text from PDF using C# and Spire.PDF for .NET, a powerful library for reading and processing PDF documents. You’ll learn how to:
- Extract full-text content from entire documents
- Retrieve text from individual pages
- Capture content within defined regions
- Obtain position and font metadata for advanced use cases
Whether you're building a PDF parser, developing an automated document management system, or migrating PDF data into structured formats, this article provides ready-to-use C# code examples and best practices to help you extract text from PDFs quickly, accurately, and at scale.
Table of Contents
- Why Use Spire.PDF for Text Extraction in .NET?
- Extract Text from PDF (Basic Example)
- Advanced Text Extraction Options
- Conclusion
- FAQs
Why Use Spire.PDF for Text Extraction in .NET?
Spire.PDF for .NET is a feature-rich and developer friendly library that supports seamless text extraction from PDFs in .NET applications. Here's why it stands out:
- Precise Layout Preservation: Maintains original layout, spacing, and reading order.
- Detailed Extraction: Retrieve text along with its metadata like position and size.
- No Adobe Dependency: Works independently of Adobe Acrobat or other third-party tools.
- Quick Integration: Clean API and extensive documentation for faster development.
Installation
Before getting started, install the library in your project via NuGet:
Install-Package Spire.PDF
Or download the DLL and manually reference it in your solution.
Extract Text from PDF (Basic Example)
Extract full text content from a PDF is crucial for capturing all information for analysis or processing.
This basic example extracts all text content from a PDF file uses the PdfTextExtractor class and saves it to a text file with the original spacing, line breaks and layout preserved.
using Spire.Pdf;
using Spire.Pdf.Texts;
using System.IO;
using System.Text;
namespace ExtractAllTextFromPDF
{
internal class Program
{
static void Main(string[] args)
{
// Create a PDF document instance
PdfDocument pdf = new PdfDocument();
// Load the PDF file
pdf.LoadFromFile("Sample.pdf");
// Initialize a StringBuilder to hold the extracted text
StringBuilder extractedText = new StringBuilder();
// Loop through each page in the PDF
foreach (PdfPageBase page in pdf.Pages)
{
// Create a PdfTextExtractor for the current page
PdfTextExtractor extractor = new PdfTextExtractor(page);
// Set extraction options
PdfTextExtractOptions option = new PdfTextExtractOptions
{
IsExtractAllText = true
};
// Extract text from the current page
string text = extractor.ExtractText(option);
// Append the extracted text to the StringBuilder
extractedText.AppendLine(text);
}
// Save the extracted text to a text file
File.WriteAllText("ExtractedText.txt", extractedText.ToString());
// Close the PDF document
pdf.Close();
}
}
}
Advanced Text Extraction Options
Spire.PDF offers more than basic full-document extraction. It supports advanced scenarios like retrieving text from specific pages, extracting content from defined areas, and accessing text layout details such as position and dimensions. This section explores these capabilities with practical examples.
Retrieve Text from Individual PDF Pages
Sometimes, you only need text from a particular page—for example, when processing a specific section of a multi-page document. You can access the desired page from the Pages collection of the document and then apply the extraction logic to it.
using Spire.Pdf;
using Spire.Pdf.Texts;
using System.IO;
namespace ExtractTextFromIndividualPages
{
internal class Program
{
static void Main(string[] args)
{
// Create a PDF document instance
PdfDocument pdf = new PdfDocument();
// Load the PDF file
pdf.LoadFromFile("Sample.pdf");
// Access the page to extract text from (e.g., index 1 = the second page)
PdfPageBase page = pdf.Pages[1];
// Create a PdfTextExtractor for the selected page
PdfTextExtractor extractor = new PdfTextExtractor(page);
// Set extraction options
PdfTextExtractOptions option = new PdfTextExtractOptions
{
IsExtractAllText = true
};
// Extract text from the specified page
string text = extractor.ExtractText(option);
// Save the extracted text to a text file
File.WriteAllText("IndividualPage.txt", text);
// Close the PDF document
pdf.Close();
}
}
}
Read Text within a Defined Area on a PDF Page
If you're interested in text within a specific rectangular area (e.g., header or footer), you can set a rectangular extraction region via PdfTextExtractOptions.ExtractArea to limit the extraction scope.
using Spire.Pdf;
using Spire.Pdf.Texts;
using System.IO;
using System.Drawing;
namespace ExtractTextFromDefinedArea
{
internal class Program
{
static void Main(string[] args)
{
// Create a PDF document instance
PdfDocument doc = new PdfDocument();
// Load the PDF file
doc.LoadFromFile("Sample.pdf");
// Get the second page
PdfPageBase page = doc.Pages[1];
// Create a PdfTextExtractor for the selected page
PdfTextExtractor textExtractor = new PdfTextExtractor(page);
// Set extraction options with a defined rectangular area
PdfTextExtractOptions extractOptions = new PdfTextExtractOptions
{
ExtractArea = new RectangleF(0, 0, 890, 170)
};
// Extract text from the specified rectangular area
string text = textExtractor.ExtractText(extractOptions);
// Save the extracted text to a text file
File.WriteAllText("Extracted.txt", text);
// Close the PDF document
doc.Close();
}
}
}
Get Text Position and Size Information for Advanced Processing
For advanced tasks like annotation or content overlay, accessing the position and size of each text fragment is crucial. You can obtain this information using PdfTextFinder and PdfTextFragment.
using Spire.Pdf;
using Spire.Pdf.Texts;
using System;
using System.Collections.Generic;
using System.Drawing;
namespace ExtractTextWithPositionAndSize
{
class Program
{
static void Main(string[] args)
{
// Load the PDF document
PdfDocument pdf = new PdfDocument();
pdf.LoadFromFile("Sample.pdf");
// Iterate through each page of the document
for (int i = 0; i < pdf.Pages.Count; i++)
{
PdfPageBase page = pdf.Pages[i];
// Create a PdfTextFinder object for the current page
PdfTextFinder finder = new PdfTextFinder(page);
// Find all text fragments on the page
List<PdfTextFragment> fragments = finder.FindAllText();
Console.WriteLine($"Page {i + 1}:");
// Iterate over each text fragment
foreach (PdfTextFragment fragment in fragments)
{
// Extract text content
string text = fragment.Text;
// Get bounding rectangles with position and size
RectangleF[] rects = fragment.Bounds;
Console.WriteLine($"Text: \"{text}\"");
// Iterate through each rectangle for this fragment
foreach (var rect in rects)
{
Console.WriteLine($"Position: ({rect.X}, {rect.Y}), Size: ({rect.Width} x {rect.Height})");
}
Console.WriteLine();
}
}
}
}
}
Conclusion
Whether you're performing simple extraction or building advanced document automation tools, Spire.PDF for .NET provides versatile and accurate methods to extract and manipulate PDF text:
- Full-text extraction for complete documents
- Page-level control to isolate relevant sections
- Area-based targeting for structured or repeated patterns
- Precise layout data for custom rendering and analysis
By combining these techniques, you can create powerful and flexible PDF processing workflows tailored to your application's needs.
FAQs
Q1: Can Spire.PDF extract text from password-protected PDFs?
A1: Yes, by providing the correct password when loading the documents, Spire.PDF can open and extract text from secured PDFs.
Q2: Does Spire.PDF support batch extraction?
A2: Absolutely. You can iterate over a directory of PDF files and apply the same extraction logic programmatically.
Q3: Can it extract font styles and sizes?
A3: Yes. Spire.PDF allows you to retrieve font-related details such as font name, size, style.
Q4: Can I extract images or tables as well?
A4: While text extraction is the focus of this guide, Spire.PDF can also extract images and supports table detection with additional logic.
Q5: Can Spire.PDF extract text from scanned (image-based) PDFs?
A5: Scanned PDFs require OCR (Optical Character Recognition). Spire.PDF doesn't provide built-in OCR, but you can combine it with an OCR library - Spire.OCR for image-to-text conversion.
Get a Free License
To fully experience the capabilities of Spire.PDF for .NET without any evaluation limitations, you can request a free 30-day trial license.
After searching so much information about PDF merge, it is easy to find that whether you merge PDF files online or use C#/VB.NET to realize this task, you never escape worrying some important points such as the safety of your PDF file, so much time it costs or whether the merged file supports to print page number and so on. However, as long as you come here, these troubles will not appear. This section will specifically introduce you a secure solution to merge PDF files into one with C#, VB.NET via a .NET PDF component Spire.PDF for .NET.
Spire.PDF for .NET, built from scratch in C#, enables programmers and developers to create, read, write and manipulate PDF documents in .NET applications without using Adobe Acrobat or any external libraries. Using Spire.PDF for .NET, you not only can quickly merge PDF files but also enables you to print PDF page with page number. Now please preview the effective screenshot below:
Before following below procedure, please download Spire.PDF for .NET and install it on system.
Step1: You can use the String array to save the names of the three PDF files which will be merged into one PDF and demonstrate Spire.Pdf.PdfDocument array. Then, load three PDF files and select the first PdfDocument for the purpose of merging the second and third PDF file to it. In order to import all pages from the second PDF file to the first PDF file, you need to call the method public void AppendPage(PdfDocument doc). Also by calling another method public PdfPageBase InsertPage(PdfDocument doc, int pageIndex),every page of the third PDF file can be imported to the first PDF file.
private void button1_Click(object sender, EventArgs e)
{
//pdf document list
String[] files = new String[]
{
@"..\PDFmerge0.pdf",
@"..\ PDFmerge1.pdf",
@"..\ PDFmerge2.pdf"
};
//open pdf documents
PdfDocument[] docs = new PdfDocument[files.Length];
for (int i = 0; i < files.Length; i++)
{
docs[i] = new PdfDocument(files[i]);
}
//append document
docs[0].AppendPage(docs[1]);
//import PDF pages
for (int i = 0; i < docs[2].Pages.Count; i = i + 2)
{
docs[0].InsertPage(docs[2], i);
}
Private Sub button1_Click(sender As Object, e As EventArgs)
'pdf document list
Dim files As [String]() = New [String]() {"..\PDFmerge0.pdf", "..\ PDFmerge1.pdf", "..\ PDFmerge2.pdf"}
'open pdf documents
Dim docs As PdfDocument() = New PdfDocument(files.Length - 1) {}
For i As Integer = 0 To files.Length - 1
docs(i) = New PdfDocument(files(i))
Next
'append document
docs(0).AppendPage(docs(1))
'import PDF pages
Dim j As Integer = 0
While j < docs(2).Pages.Count
docs(0).InsertPage(docs(2), j)
j = j + 2
End While"
Step2: Draw page number in the first PDF file. In this step, you can set PDF page number margin by invoking the class Spire.Pdf.Graphics. PdfMargins. Then, Call the custom method DrawPageNumber(PdfPageCollection pages, PdfMargins margin, int startNumber, int pageCount) to add page number in the bottom of every page in the first PDF. Please see the detail code below:
//set PDF margin
PdfUnitConvertor unitCvtr = new PdfUnitConvertor();
PdfMargins margin = new PdfMargins();
margin.Top = unitCvtr.ConvertUnits(2.54f, PdfGraphicsUnit.Centimeter, PdfGraphicsUnit.Point);
margin.Bottom = margin.Top;
margin.Left = unitCvtr.ConvertUnits(3.17f, PdfGraphicsUnit.Centimeter, PdfGraphicsUnit.Point);
margin.Right = margin.Left;
this.DrawPageNumber(docs[0].Pages, margin, 1, docs[0].Pages.Count);
private void DrawPageNumber(PdfPageCollection pages, PdfMargins margin, int startNumber, int pageCount)
{
foreach (PdfPageBase page in pages)
{
page.Canvas.SetTransparency(0.5f);
PdfBrush brush = PdfBrushes.Black;
PdfPen pen = new PdfPen(brush, 0.75f);
PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 9f, System.Drawing.FontStyle.Italic), true);
PdfStringFormat format = new PdfStringFormat(PdfTextAlignment.Right);
format.MeasureTrailingSpaces = true;
float space = font.Height * 0.75f;
float x = margin.Left;
float width = page.Canvas.ClientSize.Width - margin.Left - margin.Right;
float y = page.Canvas.ClientSize.Height - margin.Bottom + space;
page.Canvas.DrawLine(pen, x, y, x + width, y);
y = y + 1;
String numberLabel
= String.Format("{0} of {1}", startNumber++, pageCount);
page.Canvas.DrawString(numberLabel, font, brush, x + width, y, format);
page.Canvas.SetTransparency(1);
}
}
'set PDF margin
Dim unitCvtr As New PdfUnitConvertor()
Dim margin As New PdfMargins()
margin.Top = unitCvtr.ConvertUnits(2.54F, PdfGraphicsUnit.Centimeter, PdfGraphicsUnit.Point)
margin.Bottom = margin.Top
margin.Left = unitCvtr.ConvertUnits(3.17F, PdfGraphicsUnit.Centimeter, PdfGraphicsUnit.Point)
margin.Right = margin.Left
Me.DrawPageNumber(docs(0).Pages, margin, 1, docs(0).Pages.Count)
Private Sub DrawPageNumber(pages As PdfPageCollection, margin As PdfMargins, startNumber As Integer, pageCount As Integer)
For Each page As PdfPageBase In pages
page.Canvas.SetTransparency(0.5F)
Dim brush As PdfBrush = PdfBrushes.Black
Dim pen As New PdfPen(brush, 0.75F)
Dim font As New PdfTrueTypeFont(New Font("Arial", 9F, System.Drawing.FontStyle.Italic), True)
Dim format As New PdfStringFormat(PdfTextAlignment.Right)
format.MeasureTrailingSpaces = True
Dim space As Single = font.Height * 0.75F
Dim x As Single = margin.Left
Dim width As Single = page.Canvas.ClientSize.Width - margin.Left - margin.Right
Dim y As Single = page.Canvas.ClientSize.Height - margin.Bottom + space
page.Canvas.DrawLine(pen, x, y, x + width, y)
y = y + 1
Dim numberLabel As [String] = [String].Format("{0} of {1}", System.Math.Max(System.Threading.Interlocked.Increment(startNumber),startNumber - 1), pageCount)
page.Canvas.DrawString(numberLabel, font, brush, x + width, y, format)
page.Canvas.SetTransparency(1)
Next
End Sub
The PDF merge code can be very long when you view it at first sight, actually, if you do not need to add page number in your merged PDF, steps two should be avoided. However, in many cases, page number brings great convenience for users to read PDF as well as print it. Spire.PDF for .NET can satisfy both your requirements of merging PDF files and adding page numbers in the merged PDF file.
The sample demonstrates how to set PDF properties for Silverlight via Spire.PDF.
The sample demonstrates how to Create Excel file for Silverlight via Spire.XLS.
The sample demonstrates how to add bookmark into Word for Silverlight via Spire.Doc.
Table in Microsoft Word is used to present data information which can assist to explain specified paragraph contents. In order to have a better appearance, people can set Word table style. This guide shows how to use Spire.Doc to set table style in Word with C#/VB.NET.
Download Spire.Doc (or Spire.Office) with .NET Framework 2.0 (or above) together. Once make sure Spire.Doc (or Spire.Office) are correctly installed on system, follow the steps below to set Word table style
In this example, a Word document with table has been prepared. It is a student transcript template from Office.com.
Step 1: Create a C#/VB.NET project in Visual Studio. Add Spire.Doc.dll as reference.
Document document = new Document(); document.LoadFromFile(@"E:\work\Documents\Student Transcript.docx");
Dim document As New Document()
document.LoadFromFile("E:\work\Documents\Student Transcript.docx")
Step 2: Set Table Style
Get table which you want to set style
Because table1 type is different from document.Sections[0].Tables[1] type, so use (Table) to transformed forcibly.
Table table1 = (Table)document.Sections[0].Tables[1];
Dim table1 As Table = CType(document.Sections(0).Tables(1), Table)
Set table row height.
table1.Rows[0].Height = 25;
table1.Rows(0).Height = 25
Set Table Style
In order to have distinction. Keep the first cell in first row as before and set style for the second cell. Firstly, set alignment and background color for the second cell. Secondly, declare a paragraph style, including font size, color and apply this style in cell.
table1.Rows[0].Cells[1].CellFormat.VerticalAlignment = VerticalAlignment.Middle; table1.Rows[0].Cells[1].CellFormat.BackColor = Color.LimeGreen; ParagraphStyle style = new ParagraphStyle(document); style.Name = "TableStyle"; style.CharacterFormat.FontSize = 14; style.CharacterFormat.TextColor = Color.GhostWhite; document.Styles.Add(style); table1.Rows[0].Cells[1].Paragraphs[0].ApplyStyle(style.Name);
table1.Rows(0).Cells(1).CellFormat.VerticalAlignment = VerticalAlignment.Middle table1.Rows(0).Cells(1).CellFormat.BackColor = Color.LimeGreen Dim style As New ParagraphStyle(document) style.Name = "TableStyle" style.CharacterFormat.FontSize = 14 style.CharacterFormat.TextColor = Color.GhostWhite document.Styles.Add(style) table1.Rows(0).Cells(1).Paragraphs(0).ApplyStyle(style.Name)
Step 3: Save and Launch
document.SaveToFile("WordTable.docx", FileFormat.Docx);
System.Diagnostics.Process.Start("WordTable.docx");
document.SaveToFile("WordTable.docx", FileFormat.Docx)
System.Diagnostics.Process.Start("WordTable.docx")
Effective Screenshot:
This guide shows how to set Word table style such as size and color via Spire.Doc. However, Spire.Doc can do a lot on operating Word document Click to learn more
Sorting data in Excel is a fundamental skill that enhances data organization and analysis. By rearranging rows based on specific criteria—such as alphabetical order, numerical value, or date—users can easily identify trends, patterns, and outliers. In this article, you will learn how to sort data in Excel using C# with Spire.XLS for .NET.
Install Spire.XLS for .NET
To begin with, you need to add the DLL files included in the Spire.XLS for .NET package as references in your .NET project. The DLL files can be either downloaded from this link or installed via NuGet.
PM> Install-Package Spire.XLS
Sort a Single Column in Excel in C#
Sorting a single column in Excel enables quick organization of your data in ascending or descending order for easier analysis. However, this method leaves other columns unchanged, potentially leading to misalignment of related data.
Spire.XLS for .NET provides the Workbook.DataSorter.SortColumns.Add(int key, SortComparisonType sortComparisonType, OrderBy orderBy) method. This method enables developers to set sorting criteria by selecting a specific column, defining the comparison type, and specifying the sort order (ascending or descending). To apply the sorting to the defined range, use the Workbook.DataSorter.Sort(CellRange range) method.
Here are the steps to sort a single column in Excel using C#:
- Create a Workbook object.
- Load an Excel file using the Workbook.LoadFromFile() method.
- Get a specific worksheet using the Workbook.Worksheets[index] property.
- Get the column where you want to sort data using the Worksheet.Range property.
- Create sorting criteria for the selected column using the Workbook.DataSorter.SortColumns.Add() method.
- Execute sorting within the column using the Workbook.DataSorter.Sort() method.
- Save the workbook to a different Excel file.
- C#
using Spire.Xls;
namespace SortSingleColumn
{
class Program
{
static void Main(string[] args)
{
// Create a Workbook object
Workbook workbook = new Workbook();
// Load an Excel file
workbook.LoadFromFile("C:\\Users\\Administrator\\Desktop\\Input.xlsx");
// Get a specific worksheet
Worksheet sheet = workbook.Worksheets[0];
// Get the cell range (a single column) where you want to sort data
CellRange cellRange = sheet.Range["F1:F6"];
// Sort values in the specified column in descending order
workbook.DataSorter.SortColumns.Add(5, SortComparsionType.Values, OrderBy.Descending);
// Sort in the specified cell range
workbook.DataSorter.Sort(cellRange);
// Save the workbook
workbook.SaveToFile("SortSingleColumn.xlsx", ExcelVersion.Version2013);
// Dispose resources
workbook.Dispose();
}
}
}
Sort Multiple Columns in Excel in C#
Sorting data across multiple columns ensures that all related data across the selected columns remains aligned and meaningful, which is useful for complex datasets where relationships between data points matter.
Sorting data across multiple columns is similar to sorting a single column. The main difference lies in the CellRange parameter used in Workbook.DataSorter.Sort(CellRange range), which specifies multiple columns instead of just one.
Here are the steps to sort multiple column in Excel using C#:
- Create a Workbook object.
- Load an Excel file using the Workbook.LoadFromFile() method.
- Get a specific worksheet using the Workbook.Worksheets[index] property.
- Get the cell range (columns) where you want to sort data using the Worksheet.Range property.
- Create sorting criteria for the selected column using the Workbook.DataSorter.SortColumns.Add() method.
- Execute sorting within the range using the Workbook.DataSorter.Sort() method.
- Save the workbook to a different Excel file.
- C#
using Spire.Xls;
namespace SortMultipleColumns
{
class Program
{
static void Main(string[] args)
{
// Create a new workbook
Workbook workbook = new Workbook();
// Load an Excel file
workbook.LoadFromFile("C:\\Users\\Administrator\\Desktop\\Input.xlsx");
// Get a specific worksheet
Worksheet sheet = workbook.Worksheets[0];
// Get the cell range (multiple columns) where you want to sort data
CellRange cellRange = sheet.Range["A1:F6"];
// Sort values in the specified column in descending order
workbook.DataSorter.SortColumns.Add(5, SortComparsionType.Values, OrderBy.Descending);
// Sort in the specified cell range
workbook.DataSorter.Sort(cellRange);
// Save the workbook
workbook.SaveToFile("SortMultipleColumns.xlsx", ExcelVersion.Version2013);
// Dispose resources
workbook.Dispose();
}
}
}
Sort by a Custom List in C#
Sorting by a custom list in Excel allows you to arrange data based on specific, non-alphabetical criteria tailored to your needs, ensuring the order is meaningful for your analysis or reporting.
To accomplish this, create an array of strings that defines the custom sorting order. Next, set the sorting criteria using the Workbook.DataSorter.SortColumns.Add(int key, OrderBy orderBy) method. Finally, invoke the Workbook.DataSorter.Sort(CellRange range) method to sort the specified cell range.
Here are the steps to sort data by a custom list in Excel using C#:
- Create a Workbook object.
- Load an Excel file using the Workbook.LoadFromFile() method.
- Get a specific worksheet using the Workbook.Worksheets[index] property.
- Get the cell range where you want to sort data using the Worksheet.Range property.
- Define the custom sorting order with an array of strings.
- Create sorting criteria for the selected column using the Workbook.DataSorter.SortColumns.Add() method.
- Execute sorting within the range using the Workbook.DataSorter.Sort() method.
- Save the workbook to a different Excel file.
- C#
using Spire.Xls;
namespace SortMultipleColumns
{
class Program
{
static void Main(string[] args)
{
// Create a new workbook
Workbook workbook = new Workbook();
// Load an Excel file
workbook.LoadFromFile("C:\\Users\\Administrator\\Desktop\\Input.xlsx");
// Get a specific worksheet
Worksheet sheet = workbook.Worksheets[0];
// Get the cell range where you want to sort data
CellRange cellRange = sheet.Range["A1:F6"];
String[] customList = { "Central", "North", "South", "East", "West" };
// Sort a specified column using the custom list
workbook.DataSorter.SortColumns.Add(0, customList);
// Sort in the specified cell range
workbook.DataSorter.Sort(cellRange);
// Save the workbook
workbook.SaveToFile("SortByCustomList.xlsx", ExcelVersion.Version2013);
// Dispose resources
workbook.Dispose();
}
}
}
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