Send text file to MScomm port in C#

Question

How do i send text file to Mscomm port.
When i open hyper terminal..reading is seen only when i transfer->send text file->5.txt.
If i rename or try using any other text file i dont get the reading.Only 5.txt file.
Now i need to implement this in C#.
How do i send this text file in C#?

Thanks in advance