ASP.NET also supports single-source Web forms. As the name implies, a single-source Web form has its code and HTML stored in the same single file. Many of the ASP.NET code samples and tutorials posted on the Web use single-source files because they are easier to distribute and display. For example, the following single-source Web form calculates the area of a circle:
Visual Basic .NET
<%@ Page Language="VB" %>
<script runat="server">
Private Sub butCalculate_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs)
' Declare variables.
Dim dblCircArea, dblRadius As Double
' Convert text input to a double (optional).
If txtRadius.Text <> "" Then _
dblRadius = System.Convert.ToDouble(txtRadius.Text)
' Calculate area.
dblCircArea = System.Math.PI * System.Math.Pow(dblRadius, 2)
' Display result.
ShowResult(dblCircArea)
End Sub
Sub ShowResult(ByVal Result As Double)
litResult.Text = "<h3>Results</h3>"
litResult.Text += "<p>The circle's area is: <b>" + Result.ToString() _
+ "</b>"
End Sub
</script>
<html>
<head>
<title>Calculate Area</title>
</head>
<body>
<form runat="server">
<h2>Calculate Area
</h2>
<hr />
Circle radius:
<asp:TextBox id="txtRadius" Runat="server"></asp:TextBox>
<asp:Button id="butCalculate" onclick="butCalculate_Click" Runat="server"
Text="Calculate"></asp:Button>
<p>
<asp:Literal id="litResult" Runat="server"></asp:Literal>
</p>
</form>
</body>
</html>
Visual C#
<%@ Page Language="C#" %>
<script runat="server">
private void butCalculate_Click(object sender, EventArgs e)
{
// Declare variables.
double dblCircArea, dblRadius;
// Convert text input to a double (optional).
if (txtRadius.Text != "")
{
dblRadius = Convert.ToDouble(txtRadius.Text);
// Calculate area.
dblCircArea = 2 * Math.PI * Math.Pow(dblRadius, 2);
// Display result.
ShowResult(dblCircArea);
}
}
void ShowResult(double Result)
{
litResult.Text = "<h3>Results</h3>";
litResult.Text += "<p>The circle's area is: <b>" + Result.ToString() +
"</b>";
}
</script>
<html>
<head>
<title>Calculate Area</title>
</head>
<body>
<form runat="server">
<h2>Calculate Area
</h2>
<hr />
Circle radius:
<asp:TextBox id="txtRadius" Runat="server"></asp:TextBox>
<asp:Button id="butCalculate" onclick="butCalculate_Click" Runat="server"
Text="Calculate"></asp:Button>
<p>
<asp:Literal id="litResult" Runat="server"></asp:Literal>
</p>
</form>
</body>
</html>
Visual Studio can edit and even run these single-source Web forms; however, the advanced features like autocomplete are not enabled for any of the code entered between the <script> and </script> elements on the page. For this reason, the code samples in this book are shown as code-behind files.
Tidak ada komentar:
Posting Komentar