Get PDF Page Number

private void DisplayPDFPageNumber(string FilePath)

{

AcroPDDocClass objPages = new AcroPDDocClass();

objPages.Open(FilePath);

TotalPDFPages = objPages.GetNumPages();

objPages.Close();

AcroAVDocClass avDoc = new AcroAVDocClass();

avDoc.Open(FilePath, "Title");

IAFormApp formApp = new AFormAppClass();

IFields myFields = (IFields)formApp.Fields;

blkPg = new string[TotalPDFPages];

firstPageNumber = myFields.ExecuteThisJavascript("event.value=this.getPageLabel(0);");

long lst = TotalPDFPages - 1;

lastPageNumber = myFields.ExecuteThisJavascript("event.value=this.getPageLabel('" + lst + "');");

avDoc.Close(0);

}