Excel InStr Function opposite direction - vba

Question

I have this VBA code that I am using to compare two columns in my Excel spreadsheet, column B to column A. It then "highlights" the ones that are missing from column A but in column B.
What I can't figure out is how to reverse the procedure to search column B and highlight the ones in column A that are different.
Original Code:
For i = 2 To LastRow
For j = 2 To LastRow
If Report.Cells(i, 2).Value <> "" Then 'This will omit blank cells at the end (in the event that the column lengths are not equal.
If InStr(1, Report.Cells(j, 1).Value, Report.Cells(i, 2).Value, vbTextCompare) > 0 Then
Report.Cells(i, 2).Interior.Color = xlNone 'Transparent background
Report.Cells(i, 2).Font.Color = RGB(0, 0, 0) 'Black font color
Exit For
Else
Report.Cells(i, 2).Interior.Color = RGB(156, 0, 6) 'Dark red background
Report.Cells(i, 2).Font.Color = RGB(255, 199, 206) 'Light red font color
End If
End If
Next j
Next i
I have tried renaming the letters and switching the column values and got close but realized that it was using the values from the original search and just highlighting the corresponding cells in column A.

Answer 1

To answer your question:
For j = 2 To LastRow
For i = 2 To LastRow
If Report.Cells(j, 1).Value <> "" Then 'This will omit blank cells at the end (in the event that the column lengths are not equal.
If InStr(1, Report.Cells(i, 2).Value, Report.Cells(j, 1).Value, vbTextCompare) > 0 Then
Report.Cells(j, 1).Interior.Color = xlNone 'Transparent background
Report.Cells(j, 1).Font.Color = RGB(0, 0, 0) 'Black font color
Exit For
Else
Report.Cells(j, 1).Interior.Color = RGB(156, 0, 6) 'Dark red background
Report.Cells(j, 1).Font.Color = RGB(255, 199, 206) 'Light red font color
End If
End If
Next i
Next j
If you wanted to used conditional formatting which makes the color changes live you can replace both loop with:
With Report.Range("A2:A" & LastRow).FormatConditions
.Delete
With .Add(Type:=xlExpression, Formula1:="=And(iserror(Vlookup(A2,B:B,1,False)),A2<>"""")")
.Font.Color = RGB(255, 199, 206)
.Interior.Color = RGB(156, 0, 6)
End With
End With
With Report.Range("B2:B" & LastRow).FormatConditions
.Delete
With .Add(Type:=xlExpression, Formula1:="=And(iserror(Vlookup(B2,A:A,1,False)),B2<>"""")")
.Font.Color = RGB(255, 199, 206)
.Interior.Color = RGB(156, 0, 6)
End With
End With
Edit the issue was that the data in Column A had an extra space at the end thus making the instr to return false.
For j = 2 To LastRow
Report.Cells(j, 1).Value = Trim(Report.Cells(j, 1).Value)
For i = 2 To LastRow
Report.Cells(i, 2).Value = Trim(Report.Cells(i, 2).Value)
If Report.Cells(j, 1).Value <> "" Then 'This will omit blank cells at the end (in the event that the column lengths are not equal.
If InStr(1, Report.Cells(i, 2).Value, Report.Cells(j, 1).Value, vbTextCompare) > 0 Then
Report.Cells(j, 1).Interior.Color = xlNone 'Transparent background
Report.Cells(j, 1).Font.Color = RGB(0, 0, 0) 'Black font color
Exit For
Else
Report.Cells(j, 1).Interior.Color = RGB(156, 0, 6) 'Dark red background
Report.Cells(j, 1).Font.Color = RGB(255, 199, 206) 'Light red font color
End If
End If
Next i
Next j
By trimming the values, the instr returned true.

Answer 2

There are many ways to accomplish this.
You could use formulas, you could create dictionaries.
A Quick solution would be:
Dim stringCount As Integer
Dim myString As String
Dim col1Range As Range
Dim col2Range As Range
Set col1Range = Report.Range("A1")
Set col2Range = Report.Range("B1")
For i = 1 To LastRow
myString = col1Range.Offset(i).Value
If myString <> "" Then
stringCount = WorksheetFunction.CountIf(Range("B:B"), myString)
If (stringCount = 0) Then
col1Range.Offset(i).Interior.Color = RGB(156, 0, 6) 'Dark red background
col1Range.Offset(i).Font.Color = RGB(255, 199, 206) 'Light red font color
Else
col1Range.Offset(i).Interior.Color = xlNone 'Transparent background
col1Range.Offset(i).Font.Color = RGB(0, 0, 0) 'Black font color
End If
End If
Next i
For j = 1 To LastRow
myString = col2Range.Offset(j).Value
If myString <> "" Then
stringCount = WorksheetFunction.CountIf(Range("A:A"), myString)
If (stringCount = 0) Then
col2Range.Offset(j).Interior.Color = RGB(156, 0, 6) 'Dark red background
col2Range.Offset(j).Font.Color = RGB(255, 199, 206) 'Light red font color
Else
col2Range.Offset(j).Interior.Color = xlNone 'Transparent background
col2Range.Offset(j).Font.Color = RGB(0, 0, 0) 'Black font color
End If
End If
Next j