Programmatically search for text in a PDF file and tell the page number?

Question

There are some tools which allow to extract the whole text portion of a PDF file in order to full text index the PDF.

What I need is a way to search for certain strings and, if thery were found in the PDF file, return the page number?

score 2 · Answer 1 · edited Apr 02 '09 at 13:44

This example uses the library included with Adobe Reader, and comes from http://www.dotnetspider.com/resources/5040-Get-PDF-Page-Number.aspx:

using Acrobat;
using AFORMAUTLib;                          
private void pdfRandD(string fPath)
{
    AcroPDDocClass objPages = new AcroPDDocClass();
    objPages.Open(fPath);
    long TotalPDFPages = objPages.GetNumPages();            
    objPages.Close();
    AcroAVDocClass avDoc = new AcroAVDocClass();
    avDoc.Open(fPath, "Title");
    IAFormApp formApp = new AFormAppClass();
    IFields myFields = (IFields)formApp.Fields;            
    string searchWord = "Search String";
    string k = "";
    StreamWriter sw = new
        StreamWriter(@"D:\KCG_FileChecker_Inputs\MAC\pdf\0230_525490_23_cha17.txt", false);
    for (int p = 0; p < TotalPDFPages; p++)
    {                
        int numWords = int.Parse(myFields.ExecuteThisJavascript("event.value=this.getPageNumWords(" + p + ");"));
        k = "";
        for (int i = 0; i < numWords; i++)
        {
            string chkWord = myFields.ExecuteThisJavascript("event.value=this.getPageNthWord(" + p + "," + i + ", true);");
            k = k + " " + chkWord;
        }                
        if(k.Trim().Contains(searchWord))
        {
           int pNum = int.Parse(myFields.ExecuteThisJavascript("event.value=this.getPageLabel(" + p + ",true);"));
           sw.WriteLine("The Word " + searchWord + " is exists in " + pNum);                    
        }

     }
     sw.Close();
     MessageBox.Show("Process completed");
}

Thanks for the code! This sample needs an installation of Adobe Professional, though. For license royalty reasons I'd rather like to have have a component to do this. — splattne, Apr 02 '09 at 13:47

Bobrovsky · Answer 2 · 2020-08-07T12:52:36.077

You can use Docotic.Pdf library to search for text in PDF files.

Following sample shows how to find specified strings in a PDF file and corresponding page numbers:

static void searchForTextStrings()
{
    string path = "";
    string[] stringsToFind = new string[] { };

    using (PdfDocument pdf = new PdfDocument(path))
    {
        for (int i = 0; i < pdf.Pages.Count; i++)
        {
            string pageText = pdf.Pages[i].GetText();
            foreach (string s in stringsToFind)
            {
                int index = pageText.IndexOf(s, 0, StringComparison.CurrentCultureIgnoreCase);
                if (index != -1)
                    Console.WriteLine("'{0}' found on page {1}", s, i);
            }
        }
    }
}

A case-sensitive search can be conducted if you remove third argument of IndexOf method.

Disclaimer: I work for Bit Miracle, vendor of the library.

Programmatically search for text in a PDF file and tell the page number?

2 Answers2