The short answer is it depends on what you are trying to do.
First I recommend watching On Double Click

That should get you started.  If you don't see what you need then come on back.
We will probably need more details including screen shots if you need to.  For instance if you want to open a specific invoice for a customer from that customers list of invoices.

As you can see I want to make a dbl click event based on the information in "Module" which is "IHC-Single" and "IHC-Multi". I have done this before with a list box (the search seminar) and it worked perfectly. Here is my code in VBA:

Select Case SearchList.Column(1)
        Case "IHC-Single":
            DoCmd.OpenForm "IHCSingleMasterMainF", , , "MasterID=" & SearchList
        
Case "IHC-Multi":
            DoCmd.OpenForm "IHCMultiMasterMainF", , , "MultiMasterID=" & SearchList

But now I want to do this in the form instead of list box.
See the form I submit.

I love Richard's VBA, it's nice when it works.

Thanks!

Dear Richard,
I can't find anything like what I want to do in the Tech help videos, would you please give me some feedback to my problem? Thanks.

Choose which field you want your users to Double Click on. In my example I use ModuleName (Module on its own is a reserved word).

Private Sub ModuleName_DblClick(Cancel As Integer)

    Select Case ModuleName
        Case "IHC-Single"
            DoCmd.OpenForm "IHCSingleMasterMainF", , , "MasterID=" & MasterID
        Case "IHC-Multi"
            DoCmd.OpenForm "IHCMultiMasterMainF", , , "MultiMasterID=" & MultiMasterID
        End Select
        
End Sub

This should get you started. If you can't get it to work we will need to know more about your table structure.

Dear Kevin,
Thank you very much. It works now. I replaced only MasterID and MultiMasterID to just ID because my source is a union query that puts both IDs AS ID. Thanks again!