Excel/VBA uncheck checkboxes if mandatory field is empty - vba

Question

I wrote a function which for each checkbox in document check if field C140 is empty if is then uncheck checkbox in same row.
Sub MarkCheckBoxes()
Dim chk As CheckBox
Dim ws As Worksheet
Set ws = ActiveSheet
For Each chk In ws.CheckBoxes
If ws.Range("C140").Value = "" Then
chk.Value = False
Else
chk.Value = True
End If
Next chk
End Sub
Now I want change it that for each row check if mandatory fields are empty if is then uncheck checkbox in the same row as empty field, also I need clean row color by:
EntireRow.Interior.ColorIndex = xlColorIndexNone
When I changed range("c140") to range("c140:c150") then I had an error mismatch..
ALSO
Ralph give me an answer for first part, but now I have another problem.
I'd like to make some function which allow me check if any of field in row 149 is text "Mandatory then it check if rows belows are empty if is then do uncheck. So I tried sth like this:
If ws.Rows("149") = "Mandatory" Then
If ws.Range("C" & chk.TopLeftCell.Row).Value
But I don't have any idea how to write second if to check value in each column

Answer 1

Use the Cells property of the Worksheet instead of the Range like this in your If statent:
If ws.Cells(3, chk.TopLeftCell).Value = ""

Answer 2

I believe you might be looking for something like this:
Sub MarkCheckBoxes()
Dim chk As CheckBox
Dim ws As Worksheet
Set ws = ActiveSheet
For Each chk In ws.CheckBoxes
If ws.Range("C" & chk.TopLeftCell.Row).Value = vbNullString Then
chk.Value = False
Else
chk.Value = True
End If
Next chk
End Sub
Explanations:
I changed merely the row for C140 to C + the row number in which the checkbox is located. I hope this is what you've been looking for.
In respect to your initial attempt to change Range("C140") (which is one cell) to a range of cells like C140:C150: of course that cannot work. That would be like please compare this apple to these 10 apples. In return you would get 10 answers some of which might be true and others might be false for your If clause. VBA wouldn't know which ones of the ture or the false to take.