VBA (Excel): If the cell is blank, copy a value from another cell. Has options if it is blank or if its a null string (which apparently are different things)

copy_if_blank_or_empty.vb

' Excel VBA Macro: This compares two columns and if a field is empty, it will copy a value from a different field.

Sub Main()

With Application ' Optimise so deleting rows doesnt hang
    .ScreenUpdating = False
    .Calculation = xlCalculationManual
End With

  ' Set up prompt input boxes for user to choose the columns
  Column1 = InputBox("Choose the column you want copied...")
  If Column1 = "" Or DelimitedColumn1 Like "*[!A-Za-z]*" Then Exit Sub
  Column2 = InputBox("Choose the column with empty cells...")
  If Column2 = "" Or Column2 Like "*[!A-Za-z]*" Then Exit Sub

    LastRow = Range("A" & Rows.Count).End(xlUp).Row ' finding last row used

    For i = LastRow To 1 Step -1 ' iterating from last row to 1st

            If IsEmpty(Range(Column2 & i).Value) Then Range(Column2 & i) = Range(Column1 & i)  ' Check if Column 1 is blank, if so Copy the value from Column 2
            If Range(Column2 & i) = vbNullString Then Range(Column2 & i) = Range(Column1 & i)  ' Check if Column 1 is a null string (""), if so Copy the value from Column 2

    Next

With Application
    .ScreenUpdating = True
    .Calculation = xlCalculationAutomatic
    .CutCopyMode = False
End With

End Sub