从数据库中检索数据的多项选择测验 - 如何从数据库中创建值进入随机的radiobuttons？

Question

我正在创建一个多项选择测验，从访问数据库中获取问题和答案。

到目前为止，我已设法将数据库连接到表单并将问题输入到radiobuttons中。

我可以标记这个问题，但到目前为止我还没有弄清楚如何随机化数据库字段以进入不同的radiobuttons。我不希望在整个问题循环中，实际答案都在同一个单选按钮中。

附件是pic

形式的图片

下面是我使用的代码。

button1是下一个按钮

button2是后退按钮

button3是保存按钮

button4是返回上一个表单按钮

button5是开始按钮

Imports System.Data.OleDb
Public Class Form1
    Dim ConnectString As String = "Provider=Microsoft.ACE.OLEDB.12.0;" & _
      " Data Source= C:\Users\Sales\Documents\Visual Studio 2010\Normalised Database.accdb"

    Dim dr As OleDbDataReader
    Dim cm As New OleDbCommand
    Dim cn As New OleDbConnection
    Dim provider As String
    Dim dataFile As String
    Dim no As Integer
    Dim q(no) As String
    Dim quesnum As Integer
    Dim answer As String
    Dim selected As String
    Dim score As Integer

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        no = InputBox("Input the number of questions you want. You can choose from 1 to 10.")
        Label1.Hide()
        Label2.Hide()
        Label3.Hide()
        RadioButton1.Hide()
        RadioButton2.Hide()
        RadioButton3.Hide()
        RadioButton4.Hide()
        Button1.Hide()
        Button2.Hide()
        Button2.Hide()
        Button3.Hide()
        Button4.Hide()

        For i = 1 To no
            question()
        Next

    End Sub

    Private Sub question()
        cn.ConnectionString = ConnectString
        cn.Open()

        quesnum = 1
        Label1.Text = "Question " & quesnum & " of " & no

        cm.CommandText = "SELECT Question, Answer1, Answer2, Answer3, CorrectAnswer FROM Question"
        cm.Connection = cn

        dr = cm.ExecuteReader

        If dr.HasRows Then
            dr.Read()
            Label2.Text = dr.Item("Question")
            RadioButton1.Text = dr.Item("Answer1")
            RadioButton2.Text = dr.Item("Answer2")
            RadioButton3.Text = dr.Item("Answer3")
            RadioButton4.Text = dr.Item("CorrectAnswer")

            dr.Close()
        End If
        cn.Close()

    End Sub

    Private Sub mark()
        cn.ConnectionString = ConnectString
        cn.Open()
        cm.CommandText = "SELECT CorrectAnswer FROM Question"
        cm.Connection = cn
        dr = cm.ExecuteReader
        If dr.HasRows Then
            dr.Read()
            answer = dr.Item("CorrectAnswer")
            dr.Close()

        End If
        cn.Close()

        If selected = answer Then score = score + 1
        MsgBox("score is " & score)
    End Sub


    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        If RadioButton1.Checked = True Then selected = RadioButton1.Text
        mark()


    End Sub


    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
        Label1.Show()
        Label2.Show()
        Label3.Show()
        RadioButton1.Show()
        RadioButton2.Show()
        RadioButton3.Show()
        RadioButton4.Show()
        Button1.Show()
        Button2.Show()
        Button3.Show()
        Button4.Show()
        Button5.Hide()
    End Sub
End Class

我也无法循环查看问题，以便在按下下一个和后退按钮时显示不同的问题和答案。

非常感谢，谢谢！

Answer 1

创建一个列表 - 例如

Dim answerList As New List(Of String)

并将您的查询结果添加到此 - 就像这样

        answerList.Items.Add(dr.Item("Answer1"))
        answerList.Items.Add(dr.Item("Answer2"))
        answerList.Items.Add(dr.Item("Answer3"))
        answerList.Items.Add(dr.Item("CorrectAnswer"))

然后这个函数随机化列表的顺序

Private Function RandomizeListOrder(answers As List(Of String)) As List(Of String)
    Dim answer2 As Integer
    Dim rnd As New Random
    'loop though each item in the list
    For answer1 As Integer = 0 To answers.Count - 1
        'pick a random answer
        answer2 = rnd.Next(0, answers.Count - 1)
        'If answer1 and answer2 are the same then skip the rest of the code
        'in the loop and go onto the next question
        If answer1 = answer2 Then
            Continue For
        End If
        'swap the questions over
        Dim temp As String
        temp = answers(answer1)
        answers(answer1) = answers(answer2)
        answers(answer2) = temp
    Next
    'return the list of answers
    Return answers
End Function

喜欢这个

answerList = RandomizeListOrder(answerList)

然后将列表的每个元素添加到单选按钮

RadioButton1.Text = answerList(0)
RadioButton2.Text = answerlist(1)
RadioButton3.Text = answerList(2)
RadioButton4.Text = answerlist(3)

哦 - 听听Plutonix - 他是明智的。

<强>更新

希望当代码添加到您的代码中时，它应该看起来像这样 - 我想。我在我的电脑上测试了这个功能，似乎工作正常。如果仍然存在错误，则可能在您的代码中某处。

Imports System.Data.OleDb
Public Class Form1
    Dim ConnectString As String = "Provider=Microsoft.ACE.OLEDB.12.0;" & _
      " Data Source= C:\Users\Sales\Documents\Visual Studio 2010\Normalised Database.accdb"

    Dim dr As OleDbDataReader
    Dim cm As New OleDbCommand
    Dim cn As New OleDbConnection
    Dim provider As String
    Dim dataFile As String
    Dim no As Integer
    Dim q(no) As String
    Dim quesnum As Integer
    Dim answer As String
    Dim selected As String
    Dim score As Integer

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        no = InputBox("Input the number of questions you want. You can choose from 1 to 10.")
        Label1.Hide()
        Label2.Hide()
        Label3.Hide()
        RadioButton1.Hide()
        RadioButton2.Hide()
        RadioButton3.Hide()
        RadioButton4.Hide()
        Button1.Hide()
        Button2.Hide()
        Button2.Hide()
        Button3.Hide()
        Button4.Hide()

        For i = 1 To no
            question()
        Next

    End Sub

    Private Sub question()
        cn.ConnectionString = ConnectString
        cn.Open()

        quesnum = 1
        Label1.Text = "Question " & quesnum & " of " & no

        cm.CommandText = "SELECT Question, Answer1, Answer2, Answer3, CorrectAnswer FROM Question"
        cm.Connection = cn

        dr = cm.ExecuteReader

        Dim answerList As New List(Of String)

        If dr.HasRows Then
            dr.Read()
            Label2.Text = dr.Item("Question")

            answerList.Items.Add(dr.Item("Answer1"))
            answerList.Items.Add(dr.Item("Answer2"))
            answerList.Items.Add(dr.Item("Answer3"))
            answerList.Items.Add(dr.Item("CorrectAnswer"))
            answerList = RandomizeListOrder(answerList)
            RadioButton1.Text = answerList(0)
            RadioButton2.Text = answerlist(1)
            RadioButton3.Text = answerList(2)
            RadioButton4.Text = answerlist(3)
            dr.Close()
        End If
        cn.Close()

    End Sub

    Private Sub mark()
        cn.ConnectionString = ConnectString
        cn.Open()
        cm.CommandText = "SELECT CorrectAnswer FROM Question"
        cm.Connection = cn
        dr = cm.ExecuteReader
        If dr.HasRows Then
            dr.Read()
            answer = dr.Item("CorrectAnswer")
            dr.Close()

        End If
        cn.Close()

        If selected = answer Then score = score + 1
        MsgBox("score is " & score)
    End Sub


    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        If RadioButton1.Checked = True Then selected = RadioButton1.Text
        mark()


    End Sub


    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
        Label1.Show()
        Label2.Show()
        Label3.Show()
        RadioButton1.Show()
        RadioButton2.Show()
        RadioButton3.Show()
        RadioButton4.Show()
        Button1.Show()
        Button2.Show()
        Button3.Show()
        Button4.Show()
        Button5.Hide()
    End Sub

    Private Function RandomizeListOrder(answers As List(Of String)) As List(Of String)
        Dim answer2 As Integer
        Dim rnd As New Random
        'loop though each item in the list
        For answer1 As Integer = 0 To answers.Count - 1
            'pick a random answer
            answer2 = rnd.Next(0, answers.Count - 1)
            'If answer1 and answer2 are the same then skip the rest of the code
            'in the loop and go onto the next question
            If answer1 = answer2 Then
                Continue For
            End If
            'swap the questions over
            Dim temp As String
            temp = answers(answer1)
            answers(answer1) = answers(answer2)
            answers(answer2) = temp
        Next
        'return the list of answers
        Return answers
    End Function

End Class