gs
   -dBATCH
   -dNOPAUSE
   -sDEVICE=txtwrite
   -dFirstPage=3
   -dLastPage=5
   -sOutputFile=-
   /path/to/your/pdf

gs
  -q
  -dNODISPLAY
  -P-
  -dSAFER
  -dDELAYBIND
  -dWRITESYSTEMDICT
  -dSIMPLE
   /path/to/ps2ascii.ps
   input.ps
  -c quit

pdftotext
   -f 13
   -l 17
   -layout
   -opw supersecret
   -upw secret
   -eol unix
   -nopgbrk
   /path/to/your/pdf
   - |less

mutool draw -F txt the.pdf

DPL.LoadFromFile(@"Sample.pdf", "");
DPL.SetOrigin(1); // Sets 0,0 coordinate position to top left of page, default is bottom left
DPL.SetTextExtractionArea(35, 35, 229, 30); // Left, Top, Width, Height
string ExtractedContent = DPL.GetPageText(8);
Console.WriteLine(ExtractedContent);