ASP.Net/Page/Postback
Demonstration of IsPostBack property (VB.net)
<% @Page Language="vb" %>
<html>
<head>
<title>IsPostBack Demonstration</title>
<script runat="server" >
Sub Page_Load(Sender As Object, e As EventArgs)
If Not IsPostBack Then
lblMessage.Text = "Before PostBack"
Else
lblMessage.Text = "Posted Back"
End If
End Sub
</script>
</head>
<body>
<h1>Demonstration of IsPostBack property</h1>
<form id="frmPostBack" runat="server">
<asp:label id="lblMessage" runat="server"/>
<asp:Button type="Submit" text="Post Back" runat="server"/>
</form>
</body>
</html>
Page IsPostBack Demo (C#)
<%@ Page Language="C#" Debug="true" %>
<script runat="server">
void Page_Load(){
if (Page.IsPostBack){
string[] choice = new string[3];
choice[0] = "1";
choice[1] = "2";
choice[2] = "3";
lblShipper.Text = "Shipper ID for " + txtShipNum.Text + " is " + Array.IndexOf(choice, txtShipNum.Text);
lblShipper.Visible = true;
}
}
</script>
<html>
<head>
<title>Array Example</title>
</head>
<body>
<form runat="server">
Please enter your shipper name.
(should be "1" or "2" or "3")
<br><asp:TextBox id="txtShipNum" runat="server" width="300px"></asp:TextBox>
<br />
Press button to find the Shipper ID number
<asp:Button id="Button1" runat="server" Text="Submit"></asp:Button>
<br />
<asp:Label id="lblShipper" runat="server"></asp:Label>
</form>
</body>
</html>
Page.IsPostBack Property (VB.net)
<%@ Page Language="vb" %>
<html>
<head>
<title>IsPostBack property example</title>
<script runat="server">
Sub Page_Load()
If Page.IsPostBack Then
Message.Text = "PostBack"
Else
Message.Text = "Non-PostBack"
End If
End Sub
</script>
</head>
<body>
<form runat="server">
<asp:button id="post" Text="Post page" runat="server"/>
<asp:label id="Message" runat="server"/>
</form>
</body>
</html>