The first method: Open Foxit Reader, go to HELP tab>Command line Help.
The second method: View the command line synatx and praramters by running command in command prompt by doing the following:
1)Launch Command Prompt as administrator.
2)In the opened Administrator:command prompt window, input
"installation directory of Foxit Reader\FoxitReader.exe" /help
Example
I have Foxit Reader installed on "C:\Program Files (x86)\Foxit Software\Foxit Reader\",I will input
"C:\Program Files (x86)\Foxit Software\Foxit Reader\FoxitReader.exe" /help
3)Press Enter key on keyboard to run this command,then you will see the command line syntax and parameters dispalyed in Command Pormpt window.