ByteScout PDF Suite – C# – Regular Expression Search and Highlight in PDF

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ByteScout PDF Suite – C# – Regular Expression Search and Highlight in PDF

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ByteScout-PDF-Suite-C-sharp-Regular-expression-search-and-highlight-in-PDF.pdf

How to Do Regular Expression Search and Highlight in PDF in C# with ByteScout PDF Suite

Learn to regular expression search and highlight in PDF in C#

Source code documentation samples give simple and easy method to install a needed feature into your application. ByteScout PDF Suite is the bundle that provides six different SDK libraries to work with PDF from generating rich PDF reports to extracting data from PDF documents and converting them to HTML. This bundle includes PDF (Generator) SDK, PDF Renderer SDK, PDF Extractor SDK, PDF to HTML SDK, PDF Viewer SDK and PDF Generator SDK for Javascript. It can regular expression search and highlight in PDF in C#.

This prolific sample source code in C# for ByteScout PDF Suite contains various functions and other necessary options you should do calling the API to regular expression search and highlight in PDF. Just copy and paste the code into your C# application’s code and follow the instructions. This basic programming language sample code for C# will do the whole work for you to regular expression search and highlight in PDF.

The trial version of ByteScout PDF Suite can be downloaded for free from our website. It also includes source code samples for C# and other programming languages.

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Program.cs

      using System.Diagnostics;
using System.Drawing;
using Bytescout.PDFExtractor;
using Bytescout.PDF;
using Pen = Bytescout.PDF.Pen;
using SolidBrush = Bytescout.PDF.SolidBrush;

namespace SearchAndHighlightExample
{
	class Program
	{
		static void Main(string[] args)
		{
			const string inputFile = @"sample.pdf";
			const int pageIndex = 0;
			const string searchPattern = "\\d+\\.\\d+";

			// Prepare TextExtractor
			using (TextExtractor textExtractor = new TextExtractor("demo", "demo"))
			{
				textExtractor.RegexSearch = true;
				textExtractor.LoadDocumentFromFile(inputFile);

				// Load document with PDF SDK
				using (Document pdfDocument = new Document(inputFile))
				{
					pdfDocument.RegistrationName = "demo";
                	pdfDocument.RegistrationKey = "demo";

					Page pdfDocumentPage = pdfDocument.Pages[pageIndex];
					Canvas canvas = pdfDocumentPage.Canvas;

					SolidBrush fillBrush = new SolidBrush(new ColorRGB(255, 0, 0));
					fillBrush.Opacity = 50; // make the brush transparent

					// Search for pattern and highlight found pieces
					if (textExtractor.Find(pageIndex, searchPattern, caseSensitive: false))
					{
						do
						{
							foreach (var foundPiece in textExtractor.FoundText.Elements)
							{
								// Inflate the rectangle a bit
								RectangleF rect = RectangleF.Inflate(foundPiece.Bounds, 1, 2);
								// Draw rectangle over the PDF page
								canvas.DrawRectangle(fillBrush, rect);
							}
						} while (textExtractor.FindNext());
					}

					// Save as new PDF document
					pdfDocument.Save("result.pdf");

					// Open result document in default associated application (for demo purposes)
					Process.Start("result.pdf");
				}
			}
		}
	}
}