ASP.Net: Check correct answer from database in Quiz Answer using C# and VB.Net

Refer below code.

HTML

<asp:Repeater ID="rptQNA" runat="server" OnItemDataBound="OnItemDataBound">
    <HeaderTemplate>
        <table class="table">
            <tr>
                <th scope="col" style="width: auto">Id </th>
                <th scope="col" style="width: auto">Question </th>
            </tr>
    </HeaderTemplate>
    <ItemTemplate>
        <tr>
            <td>
                <asp:Label ID="lblQuestionId" runat="server" Text='<%# Eval("QUESTIONID") %>'></asp:Label>
            </td>
            <td>
                <asp:Label ID="lblDescription" runat="server" Text='<%# Eval("QUESTIONDESCRIPTION") %>' Font-Bold="true"></asp:Label>
                <br />
                <asp:RadioButtonList ID="rblOptions" runat="server" BorderStyle="None">
                </asp:RadioButtonList>
            </td>
        </tr>
    </ItemTemplate>
    <FooterTemplate>
        </table>
    </FooterTemplate>
</asp:Repeater>
<br />
<asp:Button runat="server" Text="Submit" OnClick="ValidateAnswer" />
<br />
<asp:Label ID="Label1" runat="server" Text="Incorrect Answer"></asp:Label>
<br />
<asp:Label ID="Label2" runat="server" Text="Incorrect Answer"></asp:Label>
<br />
<asp:Label ID="Label3" runat="server" Text="Incorrect Answer"></asp:Label>

Namespaces

C#

using System.Data;
using System.Data.SqlClient;
using System.Configuration;

VB.Net

Imports System.Data
Imports System.Data.SqlClient
Imports System.Configuration

Code

C#

string conString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindQuestionRepeater();
    }
}

private void BindQuestionRepeater()
{
    using (SqlConnection con = new SqlConnection(conString))
    {
        string query = "SELECT QUESTIONID, QUESTIONDESCRIPTION FROM QuestionTable";
        using (SqlCommand cmd = new SqlCommand(query, con))
        {
            using (SqlDataAdapter oda = new SqlDataAdapter(cmd))
            {
                using (DataTable dt = new DataTable())
                {
                    oda.Fill(dt);
                    rptQNA.DataSource = dt;
                    rptQNA.DataBind();
                }
            }
        }
    }
}

protected void OnItemDataBound(object sender, RepeaterItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
    {
        string questionId = (e.Item.FindControl("lblQuestionId") as Label).Text;
        RadioButtonList rblOptions = e.Item.FindControl("rblOptions") as RadioButtonList;
        BindradioButtonList(questionId, rblOptions);
    }
}

private void BindradioButtonList(string questionId, RadioButtonList rblOptions)
{
    using (SqlConnection con = new SqlConnection(conString))
    {
        string query = "SELECT QUESTIONID, OPTIONS FROM OPTIONTABLE WHERE QUESTIONID = @QuestionId";
        using (SqlCommand cmd = new SqlCommand(query, con))
        {
            cmd.CommandType = CommandType.Text;
            cmd.Parameters.AddWithValue("QuestionId", questionId);
            cmd.Connection = con;
            con.Open();
            rblOptions.DataSource = cmd.ExecuteReader();
            rblOptions.DataTextField = "OPTIONS";
            rblOptions.DataValueField = "OPTIONS";
            rblOptions.DataBind();
            con.Close();
        }
    }
}

protected void ValidateAnswer(object sender, EventArgs e)
{
    foreach (RepeaterItem item in rptQNA.Items)
    {
        string id = (item.FindControl("lblQuestionId") as Label).Text;
        string answer = (item.FindControl("rblOptions") as RadioButtonList).SelectedItem.Text;
        using (SqlConnection con = new SqlConnection(conString))
        {
            string query = "SELECT QuestionId FROM AnswerTable WHERE QuestionId = @Id AND Answer = @Answer";
            using (SqlCommand cmd = new SqlCommand(query, con))
            {
                con.Open();
                cmd.Parameters.AddWithValue("@Id", id);
                cmd.Parameters.AddWithValue("@Answer", answer);
                object o = cmd.ExecuteScalar();
                con.Close();
                switch (id)
                {
                    case "1":
                        Label1.Text = o != null ? "Answer is correct." : "Incorrect Answer";
                        break;
                    case "2":
                        Label2.Text = o != null ? "Answer is correct." : "Incorrect Answer";
                        break;
                    case "3":
                        Label3.Text = o != null ? "Answer is correct." : "Incorrect Answer";
                        break;
                    default:
                        break;
                }
            }
        }
    }
}

VB.Net

Private conString As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Me.BindQuestionRepeater()
    End If
End Sub

Private Sub BindQuestionRepeater()
    Using con As SqlConnection = New SqlConnection(conString)
        Dim query As String = "SELECT QUESTIONID, QUESTIONDESCRIPTION FROM QuestionTable"
        Using cmd As SqlCommand = New SqlCommand(query, con)
            Using oda As SqlDataAdapter = New SqlDataAdapter(cmd)
                Using dt As DataTable = New DataTable()
                    oda.Fill(dt)
                    rptQNA.DataSource = dt
                    rptQNA.DataBind()
                End Using
            End Using
        End Using
    End Using
End Sub

Protected Sub OnItemDataBound(ByVal sender As Object, ByVal e As RepeaterItemEventArgs)
    If e.Item.ItemType = ListItemType.Item OrElse e.Item.ItemType = ListItemType.AlternatingItem Then
        Dim questionId As String = (TryCast(e.Item.FindControl("lblQuestionId"), Label)).Text
        Dim rblOptions As RadioButtonList = TryCast(e.Item.FindControl("rblOptions"), RadioButtonList)
        BindradioButtonList(questionId, rblOptions)
    End If
End Sub

Private Sub BindradioButtonList(ByVal questionId As String, ByVal rblOptions As RadioButtonList)
    Using con As SqlConnection = New SqlConnection(conString)
        Dim query As String = "SELECT QUESTIONID, OPTIONS FROM OPTIONTABLE WHERE QUESTIONID = @QuestionId"
        Using cmd As SqlCommand = New SqlCommand(query, con)
            cmd.CommandType = CommandType.Text
            cmd.Parameters.AddWithValue("QuestionId", questionId)
            cmd.Connection = con
            con.Open()
            rblOptions.DataSource = cmd.ExecuteReader()
            rblOptions.DataTextField = "OPTIONS"
            rblOptions.DataValueField = "OPTIONS"
            rblOptions.DataBind()
            con.Close()
        End Using
    End Using
End Sub

Protected Sub ValidateAnswer(ByVal sender As Object, ByVal e As EventArgs)
    For Each item As RepeaterItem In rptQNA.Items
        Dim id As String = (TryCast(item.FindControl("lblQuestionId"), Label)).Text
        Dim answer As String = (TryCast(item.FindControl("rblOptions"), RadioButtonList)).SelectedItem.Text
        Using con As SqlConnection = New SqlConnection(conString)
            Dim query As String = "SELECT QuestionId FROM AnswerTable WHERE QuestionId = @Id AND Answer = @Answer"
            Using cmd As SqlCommand = New SqlCommand(query, con)
                con.Open()
                cmd.Parameters.AddWithValue("@Id", id)
                cmd.Parameters.AddWithValue("@Answer", answer)
                Dim o As Object = cmd.ExecuteScalar()
                con.Close()
                Select Case id
                    Case "1"
                        Label1.Text = If(o IsNot Nothing, "Answer is correct.", "Incorrect Answer")
                    Case "2"
                        Label2.Text = If(o IsNot Nothing, "Answer is correct.", "Incorrect Answer")
                    Case "3"
                        Label3.Text = If(o IsNot Nothing, "Answer is correct.", "Incorrect Answer")
                    Case Else
                End Select
            End Using
        End Using
    Next
End Sub

Screenshot