Конвертируйте PDF в TXT в .NET SDK

    public static void ConvertPdfToText()
    {
        const string localImageFileName = @"C:\Samples\sample.pdf";
        const string storageImageFileName = "sample.pdf";
        const string resultFileName = "sample.txt";

        // Get your AppSid and AppSecret https://dashboard.aspose.cloud (free registration required).
        var pdfApi = new PdfApi(AppSecret, AppSid);
        using var file = File.OpenRead(localImageFileName);
        pdfApi.UploadFile(storageImageFileName, file);
        
        var response = pdfApi.GetText(storageImageFileName,0,0,0,0);
        var lines = response.TextOccurrences.List.Select(x=>x.Text).ToList();
        File.WriteAllLines(resultFileName, lines);
    }