Checks whether a registry key exists.
RegExistKey(handle, subkey-string [,view-flag])
(i) handle an open handle to a registration database key.
(s) subkey-string a path from the key provided to the desired key.
(i) view-flag [optional] controls which registry view the function uses when accessing the Windows registry.
0 - view indicated by the last call to the RegOpenFlags.
32 - use the 32-bit registry view.
64 - use the 64-bit registry view.
(i) @TRUE if the specified registry key exists and is accessible (i.e., can be opened with RegOpenKey). Otherwise, it returns @FALSE.
View-flag
This optional parameter controls which registry view the function uses when accessing the Windows registry. The optional parameter's values can be 32 to use the 32-bit view, 64 to use the 64-bit view, or 0 to use the view indicated by the last call to the RegOpenFlags. The parameter value of 0 can also causes a function to use the WinBatch default 64-bit view, if no call to RegOpenFlags has been made and setting the parameter to 0 is equivalent to omitting the parameter entirely.
Notes:
Using the 32 or 64 values cause these functions to error if a function's subkey parameter contains the string 'wow6432node'.
Setting the parameter to one of the valid values has no effect when running on 32-bit Windows.
key=RegExistKey(@REGCLASSES, "txtfile")
If key == 1
who=RegQueryValue(@REGCLASSES,"txtfile\shell\open\command")
Else
Message("Sorry","The specified key does not exist!")
Break
EndIf
Display(3,"Default text file editor is", who)
RegOpenKey and the section on Registration Database Operations