Question

只是想知道我为我的视觉基础计算功课做了什么是正确的。我们的活动任务：

“活动：使用案例陈述选择成绩

简介：

您将使用一个案例陈述，允许用户将等级值作为整数值输入，并将等级返回为从A到E的字母。

选择逻辑

如果输入的数字在91-100之间，则输出将为A
如果输入的数字介于81和90之间，则输出将为B
如果输入的数字介于71和80之间，则输出将为C
如果输入的数字介于61和70之间，则输出将为D
如果输入的数字介于51和60之间，则输出将为E

任何低于50 的失败
  高于100 的任何内容都是错误值，他们必须再次运行该程序。
  创建必要的变量
  创建必要的输出，告诉用户程序的目的   创建代码以读取用户的名字
  创建读取等级的代码作为整数值
  根据上述标准创建生成相关等级的代码   创建必要的输出代码，输出用户的名字，并将其成绩输出为字母“

我的代码：

Module Module1

Sub Main()
    Dim anum As Integer
    Dim name As String
    Console.WriteLine("This programme converts marks into grades")
    Console.WriteLine("Please enter name...")
    name = Console.ReadLine
    Console.WriteLine("Please enter number of marks...")
    anum = Console.ReadLine()
    Select Case anum
        Case 91 To 100
            Console.WriteLine(name & " receives an A.")
        Case 81 To 90
            Console.WriteLine(name & " receives a B.")
        Case 71 To 80
            Console.WriteLine(name & " receives a C.")
        Case 61 To 70
            Console.WriteLine(name & " receives a D.")
        Case 51 To 60
            Console.WriteLine(name & " receives an E.")
        Case Is <= 50
            Console.WriteLine(name & ", unfortunately failed.")
        Case Is > 100
            Console.WriteLine(name & ", this is an incorrect value. Please try again.")
    End Select
End Sub

End Module

如果有人能够确认它是正确的，或者告诉我是否做错了什么或者需要添加某些东西，那么会感激不尽！

感谢。

Answer 1

原始代码似乎没问题只是我使用正确的数据类型改进了它，添加了基本的异常转换，并试图简化：

Module Module1

' Store ranges and chars
ReadOnly TupleList As New List(Of Tuple(Of Short, Short, Char)) From { _
         Tuple.Create(51S, 60S, "E"c), _
         Tuple.Create(61S, 70S, "D"c), _
         Tuple.Create(71S, 80S, "C"c), _
         Tuple.Create(81S, 90S, "B"c), _
         Tuple.Create(91S, 100S, "A"c) _
}

' Set custom strings formatting
ReadOnly str_OK As String = "{0}, receives an {1}."
ReadOnly str_FAIL As String = "{0}, unfortunately failed."
ReadOnly str_INCORRECT As String = "{0}, this is an incorrect value. Please try again."

Sub Main()

    ' Initialize user variables with a default value (0)
    Dim anum As Short = 0
    Dim name As String = 0

    Console.WriteLine("This programme converts marks into grades")
    Console.WriteLine("Please enter name...")
    name = CStr(Console.ReadLine)

    Try
        Console.WriteLine("Please enter number of marks...")
        anum = CShort(Console.ReadLine())

    Catch ex As FormatException
        Console.WriteLine("Please enter a valid number...")
        Environment.Exit(1) ' Exit from application returning an error exitcode

    Catch ex As Exception
        Console.WriteLine(String.Format("{0}: {1}", _
                                        ex.Message, _
                                        ex.StackTrace))
        Environment.Exit(1) ' Exit from application returning an error exitcode

    End Try

    Select Case anum

        Case Is <= 50
            Console.WriteLine(String.Format(str_FAIL, name))

        Case Is >= 101
            Console.WriteLine(String.Format(str_INCORRECT, name))

        Case Else ' User value is inside an accepted range
            For Each Item As Tuple(Of Short, Short, Char) In TupleList
                If (anum >= Item.Item1 AndAlso anum <= Item.Item2) Then
                    Console.WriteLine(String.Format(str_OK, name, Item.Item3))
                    Environment.Exit(0) ' Exit from application
                    ' Exit For
                End If
            Next Item

    End Select

    Environment.Exit(1) ' Exit from application returning an error exitcode
    ' ( When Is <= 50 or Is >= 101 )

End Sub

End Module

Answer 2

我唯一能做的就是你的原始代码：使用“Case Else”代替“Case Is＆gt; 100”作为最终的Case语句。这样，如果有人输入的不是数字，它会处理错误。干得好，祝你好运！

使用case语句任务检查的Visual Basic选择

2 个答案: