准备一个按纽和一个文本框 Option Explicit: Dim a As IntegerPrivate Sub Command1_Click()a = Val(Text1.Text)Select Case aCase 90 To 100MsgBox "优秀"Case 80 To 89MsgBox "良好"Case 70 To 79MsgBox "中等"Case 60 To 69MsgBox "及格"Case 0 To 59MsgBox "不及格"Case ElseMsgBox "请输入一个0到100之间的数字"End SelectEnd Sub...