16
votes

It is pretty much widely accepted that this is not 'best practise'.

dim rng as range
with thisworkbook    '<~~ possibly set an external workbook 
    with .worksheets("sheet1")
        set rng = .range(cells(2, 1), cells(rows.count, 1).end(xlup))
    end with
end with

The two Range.Cells properties that define the scope of the Range object will default to the ActiveSheet property. If this is not Sheet1 (defined as the .Parent in the With ... End With statement), the assignment will fail with,

Run-tim error '1004': Application-defined or object-defined error

Solution: use .Cells not Cells. Case closed.

But...

Is the . necessary in this Range object definition when both the Range.Cells properties inherit the .Parent worksheet property that is defined in the With ... End With statement?

How can this,

dim rng as range
with thisworkbook    '<~~ possibly set an external workbook 
    with .worksheets("sheet1")
        ' define rng as Sheet1!A2 to the last populated cell in Sheet1!A:A
        set rng = .range(.cells(2, 1), .cells(rows.count, 1).end(xlup))  '<~~ .range
    end with
end with
debug.print rng.address(0, 0, external:=true)

... be different from this,

dim rng as range
with thisworkbook    '<~~ possibly set an external workbook 
    with .worksheets("sheet1")
        ' define rng as Sheet1!A2 to the last populated cell in Sheet1!A:A
        set rng = range(.cells(2, 1), .cells(rows.count, 1).end(xlup))  '<~~ range not .range
    end with
end with
debug.print rng.address(0, 0, external:=true)

We use .range when the parameters that define the scope of the range are ambiguous; e.g. .range([A1]) The A1 cell could be from any worksheet and will default to the ActiveSheet property without the .. But why do we need to reference the parent of a range object when the scope that defines it has properly referenced its parent worksheet?

3

3 Answers

20
votes

My opinion is slightly different here.

YES it is required. You can't always control where the user may run the code from.

Please consider these few test cases

SCENARIO

Workbook has 2 worksheets. Sheet1 and Sheet2


TEST 1 (Running from a module)

Both Code give same result

TEST 2 (Running from a Sheet code area of Sheet1)

Both Code give same result

TEST 3 (Running from a Sheet code area of Sheet2)

'~~> This code fails
set rng = range(.cells(2, 1), .cells(rows.count, 1).end(xlup))

You will get Application Defined or Object defined error

enter image description here

And hence it is always advisable to properly qualify your objects so that the code can run from anywhere

9
votes

No, the . is not required where the cell references inside the brackets are qualified, unless the code is in a Worksheet module. That said it is faster to run set rng = .range(.cells(...), .cells(...)) than it is to run set rng = range(.cells(...), .cells(...)) so including the . does some good.

For a Worksheet module, the . is required.

7
votes

The answer seems to be: only if the code is located in a Worksheet object. I strongly suspect that this is because the Worksheet objects are the only ones that are both extensible and have a Range function. When Range is called from a Worksheet, that object's Range function has scope. When the code is located in ThisWorkbook or a user module or class, the Range function with the closest available scope is the global Range object (assuming of course that there isn't a user defined Range function). That one is tied to the Application, which has to resolve it based on the passed parameters and forward the call to the correct Worksheet.