How can Excel VBA open file using default application - vba

Question

I want an Excel spreadsheet that has a file path and name in column A. When a macro is run, let's say the file specified in A1 should be opened on the user's machine. The file could be .doc, .xls, .txt, etc.... rather than my vba needing to know the full path the to application, how could I have the vba tell the machine "please open this file and use your application associated with the extension" ?
I have already found this to work with the full path:
dblShellReturned = Shell("C:\Windows\System32\notepad.exe myfile.txt, vbNormalFocus)
how could I get it to work with something like:
dblShellReturned = Shell("myfile.txt", vbNormalFocus) ' how do I get this to work
Thank you in advance!

Answer 1

This works for me in Excel & Word
Sub runit()
Dim Shex As Object
Set Shex = CreateObject("Shell.Application")
tgtfile = "C:\Nax\dud.txt"
Shex.Open (tgtfile)
End Sub
or ... as per Expenzor's comment below
CreateObject("Shell.Application").Open("C:\Nax\dud.txt")

Answer 2

VBA's Shell command wants an exe, so I've been launching the explorer.exe and passing in my file path as an argument. It also seems to work with *.lnk shortcuts and web urls.
Shell "explorer.exe C:\myfile.txt"

Answer 3

The code below is a template. However you might want to update the default (working) directory to the location of the file.
Declare Function ShellExecute Lib "shell32.dll" Alias "ShellExecuteA" _
(ByVal hwnd As Long, ByVal lpszOp As String, _
ByVal lpszFile As String, ByVal lpszParams As String, _
ByVal LpszDir As String, ByVal FsShowCmd As Long) _
Function StartDoc(DocName As String) As Long
Dim Scr_hDC As Long
Scr_hDC = GetDesktopWindow()
StartDoc = ShellExecute(Scr_hDC, "Open", DocName, _
"", "C:\", SW_SHOWNORMAL)
End Function

Answer 4

I can't comment on existing answers (not enough points), so I'm answering to add information.
Working from Access 2010, I ran into silent failures with the following syntax:
Dim URL As String
URL = "http://foo.com/"
CreateObject("Shell.Application").Open URL
I could get it to work if I wrapped URL in parentheses, but that just seems wrong for subroutine (instead of function) call syntax. I tried swallowing the return value, but that failed with function call syntax, unless I doubled up the parentheses. I realized that the parentheses weren't just syntactic sugar - they had to be doing something, which lead me to believe they might be facilitating implicit casting.
I noticed that Open expects a Variant, not a String. So I tried CVar, which did work. With that in mind, the follwing is my preferred approach since it minimizes the "why are there extraneous parentheses here?" questions.
Dim URL As String
URL = "http://foo.com/"
CreateObject("Shell.Application").Open CVar(URL)
The lesson is that when making OLE Automation calls, be explicit about having Access VBA cast things appropriately!

Answer 5

Shell32.Shell COM object aka Shell.Application can be used that wraps the ShellExecute Win32 API function:
Add a reference to Microsoft Shell Controls And Automation type library to VBA project via Tools->References..., then
Dim a As New Shell32.Shell
Call a.ShellExecute("desktop.ini")
Alternatively, without any references:
Call CreateObject("Shell.Application").ShellExecute("desktop.ini")
Interestingly, here (WinXP), when using a typed variable (that provides autocomplete), ShellExecute is missing from the members list (but works nonetheless).