Merge pull request #521 from telerik/new-kb-split-big-pdf-documents-750b1b4135724865a2445dfd8bbbf135

Added new kb article split-big-pdf-documents

Author: YoanKar

knowledge-base/images/split-big-pdf.png

@@ -0,0 +1,102 @@
+---
+title: Splitting Big PDF Documents into Smaller Files Efficiently
+description: Learn how to efficiently export subsets of pages from a RadFixedDocument to handle large PDFs by splitting them into smaller chunks using PdfStreamWriter.
+type: how-to
+page_title: How to Split Large PDFs into Smaller Chunks Using RadPdfProcessing
+slug: split-big-pdf-documents
+tags: pdf, large, big, slow, memory, split, document, processing
+res_type: kb
+ticketid: 1679749
+---
+
+## Environment
+
+| Version | Product | Author | 
+| ---- | ---- | ---- | 
+|2025.1.205| RadPdfProcessing |[Desislava Yordanova](https://www.telerik.com/blogs/author/desislava-yordanova)| 
+
+## Description
+
+When working with large PDF documents, it might be necessary to split these documents into smaller "chunks" of a specified number of pages. This article shows a sample approach how to export efficiently subsets of pages without having to repeatedly re-import the entire document for each chunk. 
+
+## Solution
+
+To efficiently export subsets of pages from a large PDF document, the [PdfStreamWriter]({%slug radpdfprocessing-formats-and-conversion-pdf-pdfstreamwriter-overview%}) functionality of [RadPdfProcessing]({%slug radpdfprocessing-overview%}) can be leveraged. This approach significantly improves performance and reduces memory usage, making it ideal for processing large volumes of PDFs. Below is a step-by-step guide on how to split a PDF document into smaller "chunks" using `PdfStreamWriter`.
+
+### Step 1: Include Necessary Namespaces
+
+Ensure you include the necessary namespaces in your project:
+
+```csharp
+using Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Streaming;
+using Telerik.Windows.Documents.Fixed.Model;
+```
+
+### Step 2: Implement the Splitting Logic
+
+Use the following logic to split a PDF document into smaller chunks. This example splits a document into chunks of 10 pages each, but you can adjust the `pagesCount` variable to change the chunk size as needed.
+
+```csharp
+internal class Program
+{
+    public const string ResultDirName = @"..\..\..\Demo results";
+    public const string InputFileMultipageDocument = "YourLargePDF.pdf";
+    static void Main(string[] args)
+    {
+        EnsureEmptyResultDirectory();
+        SplitDocumentPages("YourLargePDF_Chunk[{0}-{1}].pdf");
+    }
+
+    private static void SplitDocumentPages(string resultFileFormat)
+    {
+        string documentToSplit = InputFileMultipageDocument;
+        int pagesCount = 10; // Number of pages per chunk
+        using (PdfFileSource fileToSplit = new PdfFileSource(File.OpenRead(documentToSplit)))
+        {
+            int totalPages = fileToSplit.Pages.Length;
+            int currentTotalPageIndex = 0;
+            int numberOfSplitDocs = totalPages / pagesCount + (totalPages % pagesCount == 0 ? 0 : 1);
+
+            for (int docIndex = 0; docIndex < numberOfSplitDocs; docIndex++)
+            {
+                int currentPagesEnd = Math.Min(currentTotalPageIndex + pagesCount, totalPages);
+                string splitDocumentName = Path.Combine(ResultDirName, string.Format(resultFileFormat, docIndex * pagesCount + 1, currentPagesEnd));
+
+                using (PdfStreamWriter fileWriter = new PdfStreamWriter(File.OpenWrite(splitDocumentName)))
+                {
+                    for (int pageIndex = currentTotalPageIndex; pageIndex < currentPagesEnd; pageIndex++)
+                    {
+                        PdfPageSource page = fileToSplit.Pages[pageIndex];
+                        fileWriter.WritePage(page);
+                        currentTotalPageIndex++;
+                    }
+                }
+            }
+        }
+    }
+
+    private static void EnsureEmptyResultDirectory()
+    {
+        if (Directory.Exists(ResultDirName))
+        {
+            foreach (string fileName in Directory.EnumerateFiles(ResultDirName))
+            {
+                File.Delete(fileName);
+            }
+        }
+        else
+        {
+            Directory.CreateDirectory(ResultDirName);
+        }
+    }
+}
+```
+
+This solution efficiently processes the splitting operation by writing each chunk directly to a new file without the need to re-import the original document multiple times:
+
+![Split Large PDF](images/split-big-pdf.png)  
+
+## See Also
+
+- [PdfStreamWriter]({%slug radpdfprocessing-formats-and-conversion-pdf-pdfstreamwriter-overview%})
+- [RadPdfProcessing]({%slug radpdfprocessing-overview%})

knowledge-base/split-big-pdf-documents.md

@@ -69,3 +69,4 @@ If the scenario requires you to read or modify the existing page content, you sh
 * [Features]({%slug radpdfprocessing-formats-and-conversion-pdf-pdfstreamwriter-features%})
 * [PdfFormatProvider]({%slug radpdfprocessing-formats-and-conversion-pdf-pdfformatprovider%})
 * [PdfStreamWriter Class]({%slug radpdfprocessing-formats-and-conversion-pdf-pdfstreamwriter-pdfstreamwriter%})
+* [Splitting Big PDF Documents into Smaller Files Efficiently]({%slug split-big-pdf-documents%})