Notepad does accept a filename as a command-line parameter. It assumes at most one filename. If you try to use multiple filenames on command line such as:
NOTEPAD file1 file2 file3
will result in notepad trying to open a file called "file1 file2 file3 (and if you try using commas as parameter separator, the commas are part of the filename it tries opening). If you use quotes around the filenames such as:
NOTEPAD "file1" "file2" "file3"
results in only file1 being opened. This means if you want ot open more than one file in notepad, you need to launch notepad separately for each file.

Although this would mean that you probably don't need to put quotes around filename if you've got embedded spaces within the filename or path to filename, I'd recommend putting quotes around the filename anyway -- just in case there is a version of notepad that behaves differently, or if someone replaces notepad with a different program (I'd seen this done on more than occasion).

>ShellExecute uses the program that is setup for a particular file type. You may try using the RUN /N command, but I don't know if you can pass the file name as a parameter to Notepad.
>
>>I am Using the follwing function to Open File through Program
>>
>>declare long ShellExecute in "shell32.dll" ; && Function to Open a File
>> long hwnd, ;
>> string lpszOp, ;
>> string lpszFile, ;
>> string lpszParams, ;
>> string lpszDir, ;
>> long nShowCmd
>>
>>lnResult = SHELLEXECUTE(0, 'open', 'master.ps', '', '', 1)
>>
>>The file is well opened in PS Viewer. However For my Program Use I want that when The User clicks, It should open in Notepad. (As I want User to Read/Write Data Inside through Notepad)
>>
>>So How to force a File to Open in Notepad ?