Private Sub CommandButton2_Click()
  Dim i As Long
  Dim m As Long, numA As Integer, numB As Integer
  Dim strA As String
  For i = 1 To [a65536].End(3).Row
      numA = InStr(Cells(i, "A"), "=")
      If numA = 0 Then GoTo numAErr0
      numB = InStr(numA, Cells(i, "A"), "-")
      If numB > 0 And IsNumeric(Mid(Cells(i, "A"), numB + 1, 1)) Then
         strA = Str(Val(Right(Cells(i, "A"), Len(Cells(i, "A")) - numB)))
         Cells(i, "A").Characters(numB, Len(strA)).Font.Color = vbRed     '如果要将某个单元格的部分字符变色，就要利用Characters(开始位置,结束位置).font.color 进行赋值
      End If
numAErr0:
  Next
End Sub