根据格中包含的特定字符改变格的填充色

用VBA如何实现，根据格中包含的特定字符“C1、C2、C3、D”，改变格的填充色！
谢谢！

Public Sub er()
Dim x As Range
For Each x In [d5:o9]
If x Like "*" & "C1" & "*" Then x.Interior.Color = vbYellow
If x Like "*" & "C2" & "*" Then x.Interior.Color = vbGreen
If x Like "*" & "C3" & "*" Then x.Interior.Color = vbBlue
If x Like "*" & "D" & "*" Then x.Interior.Color = vbRed
Next x
End Sub