what does a adobe acrobat plugin does while displaying PDF file in IE?

[C# Programming]

I want the PDF file's data when it a PDF is opened in IE.
How can I do this using c#.
The COM reference AcroIEHelper.dll is added in my project.

ACROIEHELPERLib.AcroIEHlprObjClass acroIEHlpr = new ACROIEHELPERLib.AcroIEHlprObjClass();

acroIEHlpr is an Object element. From this how can I retrieve the information of PDF opened in IE.
How can I get the text of that PDF file?