Hi Niranjan,
You can use the following function module where you will be passing the directory path and it will return all the files in that particular directory into a internal table.
CALL FUNCTION 'RZL_READ_DIR_LOCAL'
EXPORTING
name = <default directory path>
TABLES
file_tbl = <internal table holding all the files>
and you can refer the following link for reading the files....
http://www.saphub.com/files/upload-file-sap-application-server/
thanks and regards,
narayan