Course: Internet Application Development
Lab: 9B
Technology: ASP.NET Web Forms using VB.NET
Create a web form containing a ListBox with programming language options. When a user selects a language, display relevant information below using AutoPostBack and event handling.
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Problem_1.aspx.vb" Inherits="Problem_1" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Programming Language Info</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h3>Select a Programming Language:</h3>
<asp:ListBox ID="ListBoxLanguages" runat="server" AutoPostBack="True"
SelectionMode="Single" OnSelectedIndexChanged="ListBoxLanguages_SelectedIndexChanged">
<asp:ListItem>Java</asp:ListItem>
<asp:ListItem>JavaScript</asp:ListItem>
<asp:ListItem>C#</asp:ListItem>
<asp:ListItem>C++</asp:ListItem>
<asp:ListItem>C</asp:ListItem>
<asp:ListItem>Python</asp:ListItem>
<asp:ListItem>SQL</asp:ListItem>
<asp:ListItem>HTML</asp:ListItem>
<asp:ListItem>CSS</asp:ListItem>
<asp:ListItem>PHP</asp:ListItem>
</asp:ListBox>
<br /><br />
<asp:Label ID="LabelInfo" runat="server" Font-Bold="True" ForeColor="Blue" />
</div>
</form>
</body>
</html>
Partial Class Problem_1
Inherits System.Web.UI.Page
Protected Sub ListBoxLanguages_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBoxLanguages.SelectedIndexChanged
Dim selectedLanguage As String = ListBoxLanguages.SelectedItem.Text
Dim message As String = ""
Select Case selectedLanguage
Case "Java"
message = "Java is a versatile and widely-used object-oriented programming language."
Case "JavaScript"
message = "JavaScript is a scripting language primarily used for creating interactive web pages."
Case "C#"
message = "C# is a modern, object-oriented programming language developed by Microsoft."
Case "C++"
message = "C++ is an extension of C that includes object-oriented features."
Case "C"
message = "C is a general-purpose, procedural programming language."
Case "Python"
message = "Python is a high-level, interpreted language known for its simplicity and readability."
Case "SQL"
message = "SQL is a domain-specific language used for managing and querying relational databases."
Case "HTML"
message = "HTML is the standard markup language for creating web pages."
Case "CSS"
message = "CSS is used to style and layout web pages."
Case "PHP"
message = "PHP is a server-side scripting language designed for web development."
Case Else
message = "Please select a language."
End Select
LabelInfo.Text = message
End Sub
End Class
Create a dynamic table using dropdowns to choose number of rows and columns (1-10). The first column should contain dropdowns with language options. The last row should include radio button lists in each cell. Apply a border and background color to last row.
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Problem_2.aspx.vb" Inherits="Problem_2" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Dynamic Table Generator</title>
<style>
table, td {
border: 2px solid red;
border-collapse: collapse;
padding: 8px;
}
.last-row {
background-color: grey;
}
</style>
</head>
<body>
<form id="form1" runat="server">
<asp:DropDownList ID="DropDownRows" runat="server"></asp:DropDownList>
<asp:DropDownList ID="DropDownCols" runat="server"></asp:DropDownList>
<asp:Button ID="btnGenerate" runat="server" Text="Generate Table" OnClick="btnGenerate_Click" />
<br /><br />
<asp:PlaceHolder ID="PlaceHolderTable" runat="server" />
</form>
</body>
</html>
Partial Class Problem_2
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If Not IsPostBack Then
' Fill row and column dropdowns with values 1 to 10
For i As Integer = 1 To 10
DropDownRows.Items.Add(i.ToString())
DropDownCols.Items.Add(i.ToString())
Next
End If
End Sub
Protected Sub btnGenerate_Click(sender As Object, e As EventArgs)
Dim rows As Integer = Integer.Parse(DropDownRows.SelectedValue)
Dim cols As Integer = Integer.Parse(DropDownCols.SelectedValue)
Dim table As New Table()
table.BorderColor = Drawing.Color.Red
table.BorderWidth = 2
For i As Integer = 1 To rows
Dim row As New TableRow()
For j As Integer = 1 To cols
Dim cell As New TableCell()
' First column of each row: dropdown list
If j = 1 Then
Dim langDDL As New DropDownList()
langDDL.Items.Add("Urdu")
langDDL.Items.Add("English")
langDDL.Items.Add("Arabic")
langDDL.Items.Add("Chinese")
cell.Controls.Add(langDDL)
Else
cell.Text = "{" & i.ToString() & ", " & j.ToString() & "}"
End If
' Last row: radio button list in every cell
If i = rows Then
cell.CssClass = "last-row"
Dim rbl As New RadioButtonList()
rbl.RepeatDirection = RepeatDirection.Horizontal
rbl.Items.Add("1")
rbl.Items.Add("2")
rbl.Items.Add("3")
rbl.Items.Add("4")
cell.Controls.Clear()
cell.Controls.Add(rbl)
End If
row.Cells.Add(cell)
Next
table.Rows.Add(row)
Next
PlaceHolderTable.Controls.Clear()
PlaceHolderTable.Controls.Add(table)
End Sub
End Class