I am not sure if things have changed after .NET 2.0 because in .NET 2.0 I used to be able to set something like this:
<asp:Panel runat="server" Visible='<%#IIf(Some condition here, "true", "false") %>' />
I did this all the time to have a clean code behind.
Currently I am working with .NET 3.0 and I cannot for the life of me get this working. The condition which i am evaluating is not accessing any data binding fields but is as simple as checking the property of an object in the code behind.
Can anyone suggest how this inline-code should look?
UPDATE:
Here is an example of what i am trying to do. I swear something like this used to work in .NET 2.0 but it does not work now:
<%# Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title></title>
<script runat="server">
protected bool IsValid() { return true; }
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:Label Text="123" runat="server" Visible=<%#iif(IsValid(), "true", "false")%>/>
</div>
</form>
</body>
</html>
<%# indicates that you databind the control/page. So either you do
Private Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load
Me.DataBind()
End Sub
or you do it in codebehind completely(what i prefer):
Private Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load
MyPanel.Visble = YourCondition
End Sub
http://naspinski.net/post/inline-aspnet-tags-sorting-them-all-out-%283c25242c-3c253d2c-3c252c-3c252c-etc%29.aspx
You can use VB in markup and C# in codebehind
<%# Page Language="VB"
Sure.. Visual Studio goes crazy
<%# Page Language="VB" AutoEventWireup="true" CodeBehind="WebForm6.aspx.cs" Inherits="WebApplication1.WebForm6" %>
<asp:repeater id="rpt" runat="server">
<ItemTemplate>
<br />
<%# Container.DataItem %>
<br />
<%#IIf( CType(Container.DataItem, System.Int32) > 5 = 0, "true", "false") %>
<br />
<br />
</ItemTemplate>
</asp:repeater>
and C# in code behind
using System.Linq;
namespace WebApplication1
{
public partial class WebForm6 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
rpt.DataSource = Enumerable.Range(1, 29);
rpt.DataBind();
}
}
}
And what VS feels about it
Related
I am using Visual Studio 2010, VB.NET, target framework .NET 4.0.
I have a GridView which I am binding to some object collection, with a CommandField column that should allow edit of the selected row.
I am setting the EditIndex property correctly in the RowEditing eventhandler.
The problem is: When I click the "Edit" link that is generated, nothing apparently happens, the row gets rendered again in "view mode", not "edit mode".
But if I do some random postback, like clicking my "doNothing" button, the row gets rendered in "edit mode" in the next postback.
I have managed to reproduce the problem in the following code:
ASPX:
<%# Page Language="vb" AutoEventWireup="false" CodeBehind="MyForm.aspx.vb" Inherits="MySandBox.MyForm" %>
<%# Register Src="MyControl.ascx" TagName="MyControl" TagPrefix="uc1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<asp:GridView ID="gvInfrator" runat="server" AutoGenerateColumns="false">
<Columns>
<asp:CommandField ShowEditButton="true" />
<asp:BoundField HeaderText="MyField" DataField="MyField" />
</Columns>
</asp:GridView>
<asp:Button ID="btnDoNothing" runat="server" Text="Just do a postback" />
</form>
</body>
</html>
Code Behind:
Public Class MyDto
Public Property MyField As String
End Class
Public Class MyForm
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Me.BindMyData()
End Sub
Private Sub BindMyData()
Dim myData As New MyDto
myData.MyField = "My field value"
Me.gvInfrator.DataSource = New MyDto() {myData}
Me.gvInfrator.DataBind()
End Sub
Protected Sub gvInfrator_RowEditing(sender As Object, e As System.Web.UI.WebControls.GridViewEditEventArgs) Handles gvInfrator.RowEditing
Me.BindMyData()
Me.gvInfrator.EditIndex = e.NewEditIndex
End Sub
End Class
Am I doing something wrong? Is this a bug in .NET Framework 4? Is there any workaround?
You need to bind your data after you set the EditIndex of your GridView.
Protected Sub gvInfrator_RowEditing(sender As Object, e As System.Web.UI.WebControls.GridViewEditEventArgs) Handles gvInfrator.RowEditing
Me.gvInfrator.EditIndex = e.NewEditIndex
Me.BindMyData()
End Sub
I am trying to understand UpdatePanels and best practise for using them.
I am using .Net4.0 with VB.Net.
The idea is to create a conversation app for a clients website and so I have control called Convo.ascx. Code added below.
<asp:UpdatePanel runat="server">
<ContentTemplate>
<h2>Conversation</h2>
<p><asp:Literal ID="lit1" runat="server" /></p>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<asp:Button ID="Button1" runat="server" Text="Button" />
</ContentTemplate>
</asp:UpdatePanel>
Convo.ascx.vb
Partial Class Convo
Inherits System.Web.UI.UserControl
Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
lit1.Text = lit1.Text & "<p>" & TextBox1.Text & "</p>"
End Sub
End Class
On a load page (Default.aspx) I have:
<%# Page Language="VB" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="_Default" %>
<%# Reference Control="~/Convo.ascx" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<asp:scriptmanager ID="Scriptmanager1" runat="server"></asp:scriptmanager>
<div>
<asp:UpdatePanel runat="server">
<ContentTemplate>
<asp:Button ID="Button1" runat="server" Text="Add Conversation" />
<asp:PlaceHolder ID="phConversation" runat="server">
</asp:PlaceHolder>
</ContentTemplate>
</asp:UpdatePanel>
</div>
</form>
</body>
</html>
With Codebehind Default.aspx.vb as
Partial Class _Default
Inherits System.Web.UI.Page
Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
AddConvo()
End Sub
Private Sub AddConvo()
Dim getPh As New PlaceHolder
getPh = CType(Me.FindControl("phConversation"), PlaceHolder)
Dim ucConvo As New Convo
ucConvo = CType(LoadControl("~/Convo.ascx"), Convo)
getPh.Controls.Add(ucConvo)
End Sub
Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
AddConvo()
End Sub
End Class
So the Convo I add OnLoad remains on the page after extra as been added been any convo added after load is gone once the button on Convo is hit.
So my question is, how can I have these add and remain? Eventually they will be added to database but right now I am trying to understand UpdatePanels as they will become the foundation for this app.
Is there a very good explanation of multi-use UpdatePanels anywhere?
Thanks in advance
PS, im a hobbiest so only VB responses please
The issue actually isn't with the UpdatePanel, but with ASP.NET. ASP.NET web forms uses a control hierarchy for the entire page, and you are adding the controls to the hierarchy "dynamically". Since you are doing it that way, ASP.NET requires you add the control back into the control hierarchy on every postback to the server. The UpdatePanel is a way to post back to the server, and therefore you must re-add the old user controls and new ones to that hierarchy.
Essentially the UpdatePanel was added to make AJAX easy, but you still have to work within the rules of ASP.NET.
I have a GridView inside an update panel, and a AsyncFileUpload (outside the Update Panel) that I am using to upload Images. All these are in a ASPX page called using the SHOWMODALDIALOG.
What I'm tying to achieve:
1. As soon as the file upload completes, the Update Panel updates, and the gridview displays the image the user just added.
The problems I'm facing:
1. The Gridview is not refreshing, even though I have a Databind event after the file is uploaded to the database. The Update Panel is getting refreshed through the __doPostBack('UpdatePanelID',' ') in a JS called by OnClientUploadComplete (I'm checking this through a Label showing current time in the Update Panel)
2. The ModalDialog is opening a new page whenever I click on 'Save Changes' or 'Cancel' button after adding an Image. If I just open the window and click these buttons, they work fine. I did try including <base target="_self" /> in the <head>, and finally settled with window.name="xxx" onload body.
Any help is appreciated.
My code:
ASPX
<%# Page Language="VB" AutoEventWireup="false" CodeFile="RCMT0032.aspx.vb" Inherits="RCWKSHEET.RCMT0032" EnableEventValidation="false"%>
<%# Register TagPrefix="asp" Namespace="AjaxControlToolkit" Assembly="AjaxControlToolkit"%>
<html>
<head>
<base target="RCMT0032" />
<title>RCMT0032</title>
<script type="text/javascript">
function readpasseddata() {
window.name = 'RCMT0032';
var rpt = window.dialogArguments;
document.getElementById("HiddenReport").value = rpt;
}
function UploadComplete(sender, args) {
__doPostBack('gvupd', '');
}
</script>
</head>
<body onload="readpasseddata()" >
<form id="Form1" method="post" runat="server" target="RCMT0032" >
<asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server"></asp:ToolkitScriptManager>
<asp:AsyncFileUpload id="BrowserHidden" Width="1" runat="server" OnClientUploadComplete="UploadComplete" OnUploadedComplete="BrowserHidden_UploadedComplete"/>
<button class="ActionButton" id="btnSave" runat="server">Save & Exit</button>
<button class="ActionButton" id="btnClose" runat="serverCancel</button>
<asp:UpdatePanel id="gvupd" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Label runat="server" ID="Label1" />
<asp:GridView id="GridView1" Runat="server" AutoGenerateColumns="False"
AllowPaging="false" EnableViewState="true" datakeynames="Seq">
<Columns>
<asp:TemplateField HeaderText="Comments">
<ItemTemplate><asp:TextBox ID="comments" Enabled="true" MaxLength="249" TextMode="MultiLine" Text='<%# Eval("Comments") %>'/>
</asp:TemplateField>
<asp:TemplateField HeaderText="Picture">
<ItemTemplate><asp:HyperLink id="PictHyper" runat="server" Target="_blank" ImageUrl='<%# String.Format("RCMT0033.aspx?report={0}&seq={1}", Eval("ReportNumber"), Eval("Seq"))%>' NavigateUrl='<%# String.Format("RCMT0034.aspx?report={0}&seq={1}", Eval("ReportNumber"), Eval("Seq"))%>' /></ItemTemplate></asp:TemplateField>
<asp:TemplateField HeaderText="Delete">
<ItemTemplate><asp:CheckBox runat="server" ID="DeleteCB" /></ItemTemplate>
</asp:TemplateField></Columns>
</asp:GridView>
</ContentTemplate>
</asp:UpdatePanel>
</div>
</form>
</body>
</html>
THE CODE BEHIND
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.LoaD
If Not IsPostBack Then
LoadData()
DataBind()
Else
With ViewState
_intReportNumber = CInt(.Item("Report"))
_strVendorNumber = CStr(.Item("VendorNumber"))
_strStatus = CStr(.Item("Status"))
End With
End If
End Sub
Public Sub LoadData()
//GET DATA INTO DATATABLE DT
GridView1.DataSource = dt
GridView1.DataBind()
Catch err As Exception
Throw err
End Try
End Sub
Protected Sub UploadData()
If BrowserHidden.PostedFile IsNot Nothing AndAlso BrowserHidden.PostedFile.FileName <> "" Then
Try
//UPLOAD STUFF
GridView1.DataBind()
Catch ex As Exception
End Try
End If
End Sub
Protected Sub btnClose_ServerClick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClose.ServerClick
canceladd()
ScriptManager.RegisterStartupScript(Page, Me.GetType(), "onclick", "window.open('','_self',''); window.close();", True)
End Sub
Protected Sub BrowserHidden_UploadedComplete(ByVal sender As System.Object, ByVal e As AjaxControlToolkit.AsyncFileUploadEventArgs)
UploadData()
End Sub
Protected Sub gvupd_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles gvupd.Load
Label1.Text = DateTime.Now.ToString()
End Sub
Protected Sub btnSave_ServerClick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.ServerClick
FinalizeAdd()
Page.ClientScript.RegisterStartupScript(Me.GetType(), "onclick", "window.open('','_self',''); window.close();", True)
End Sub
For your #2 issue, I don't think you can reload/refresh the modal window with either client side or server side script. To archive the same or similar result, you can have the upload control to close the modal window and return a value to indicate reopening is needed. then in the parent window, you can use a loop to open it as needed. if user clicks on close button on modal window or the X button on top right, the modal will not be reopened because it does not sent the "reopen" value back to parent.
ParentPage.aspx
<%# Page Language="C#" AutoEventWireup="true" CodeBehind="ParentPage.aspx.cs" Inherits="WebApplication1.ParentPage" %>
<%# Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script type="text/javascript">
function popModal(){
var val = window.showModalDialog('ModalChild.aspx', '', '');
while (val == "reopen") {
val = window.showModalDialog('ModalChild.aspx', '', '');
}
}
</script>
</head>
<body>
<input type='button' value='Pop Modal' onclick='popModal();' />
</body>
</html>
ModalChild.aspx
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script type="text/javascript">
function closeAndReOpen(){
window.returlValue = "reopen";
window.close();
}
</script>
</head>
<body>
<form id="form1" runat="server">
<asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server">
</asp:ToolkitScriptManager>
<div>
<asp:AsyncFileUpload ID="AsyncFileUpload1" runat="server" OnClientUploadComplete="closeAndReOpen();"
OnUploadedComplete="AsyncFileUpload1_UploadedComplete" />
<input type='button' value='Close' onclick='window.close();' />
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:GridView runat="server" ID="GridView1" AutoGenerateColumns="False" OnRowDataBound="GridView1_RowDataBound">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<img runat="server" id="img" /></ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="AsyncFileUpload1" />
</Triggers>
</asp:UpdatePanel>
</div>
</form>
</body>
</html>
ModalChild.aspx.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
using System.Web.UI.HtmlControls;
namespace WebApplication1
{
public partial class ModalChild: System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
LoadGrid();
}
}
protected void LoadGrid()
{
var files = new DirectoryInfo(Server.MapPath("Data")).GetFiles("*.png");
GridView1.DataSource = files;
GridView1.DataBind();
}
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
var fi = e.Row.DataItem as FileInfo;
var img = e.Row.FindControl("img") as HtmlImage;
img.Src = #"Data\" + fi.Name;
}
}
protected void AsyncFileUpload1_UploadedComplete(object sender, AjaxControlToolkit.AsyncFileUploadEventArgs e)
{
if (AsyncFileUpload1.PostedFile != null)
{
var savePath = Server.MapPath(#"Data\" + Guid.NewGuid().ToString() + ".png");
AsyncFileUpload1.SaveAs(savePath);
}
}
}
}
Hi
I have a simple aspx file with 2 text boxes and an ajax autocomplete extender attached to textbox2
<%# Page Language="VB" AutoEventWireup="false" CodeFile="test4.aspx.vb" Inherits="test4" %>
<%# Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
<form id="form1" runat="server">
<div id="content">
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:TextBox ID="TextBox1" runat="server">
</asp:TextBox><br />
<asp:TextBox ID="TextBox2" runat="server">
</asp:TextBox>
</div>
<asp:AutoCompleteExtender ID="load_textBox2" TargetControlID="TextBox2" ServiceMethod="GetModelName"
UseContextKey="True" runat="server">
</asp:AutoCompleteExtender>
</form>
</body>
</html>
What i am trying to do is to call the pagemethod "GetModelName" form the aspx.vb to fillup the textbox2 with the relevent data
This is the aspx.vb code
Imports System.Web.Services
Partial Class test4
Inherits System.Web.UI.Page
Dim Model_Name_old As String()()
Dim mod_code As String()
Dim mod_name As String()
Dim cod_upper As Integer
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
//calling webservice that retunrs a jagged array
Dim ins As New localhost_insert_model.dbModel
Model_Name_old = ins.get_Model_Name("A")
mod_code = Model_Name_old(0)
mod_name = Model_Name_old(1)
cod_upper = Model_Name_old(0).GetUpperBound(0)
End Sub
<WebMethod()>
Public Function GetModelName() As String()
Return mod_name
End Function
End Class
This not working.. How can i make it work???.
Your function should be shared:
<WebMethod()>
Public Shared Function GetModelName() As String()
Return mod_name
End Function
Check that EnablePageMethods="true" in the script manager tag.
I am trying to learn asp.net (vb.net) and I'm having some trouble. I want to change a pages content based on the querystring.
In classic asp I would do:
<% If request.querystring("page") = 1 THEN %>
-entire page-
<% Else %>
-different page-
<% End If %>
The closest I could get in .net is
Sub Page_Load(ByVal Sender as Object, ByVal E as EventArgs)
If Request.QueryString("page") = 1 Then
lblMessage1.Text = "message"
Else
lblMessage1.Text = "message2"
End If
End Sub
That only seems good for small things. What would be the best method to change an entire page?
You could do the following (simple redirect):
If Request.QueryString("page") = 1 Then
Response.Redirect("MyPage1.aspx")
Else
Response.Redirect("MyPage2.aspx")
End If
You could also do this (read more here):
If Request.QueryString("page") = 1 Then
Server.Transfer("MyPage1.aspx")
Else
Server.Transfer("MyPage2.aspx")
End If
And finally one more option (show/hide different panels on the page):
If Request.QueryString("page") = 1 Then
MyPanel1.Visible = true
MyPanel2.Visible = false
Else
MyPanel1.Visible = false
MyPanel2.Visible = true
End If
I would suggest using the MultiView control.
In a nutshell, you would create two multiview "Views", each with the html that you would want to show. Then you could look at the querystring parameter and switch the active view of the multiview accordingly.
This has a lot of advantages to Response.Redirect() like others suggested. First off, that would always generate at least two browser requests. Also, Response.Redirect() throws a ThreadAborted exception behind the scenes, which can confuse people diagnosing the application.
Example MultiView control:
ASPX:
<form id="form1" runat="server">
<div>
<asp:MultiView ID="MultiView1" runat="server">
<asp:View runat="server">
Hi, this is Page 1
</asp:View>
<asp:View runat="server">
Hi, this is Page 2
</asp:View>
</asp:MultiView>
</div>
</form>
Code:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
If Request.QueryString("page") = "1" Then
MultiView1.ActiveViewIndex = 0
Else
MultiView1.ActiveViewIndex = 1
End If
End Sub
You really have a few options, you could:
Response.Redirect(url) to a different page based on the input.
You could have an ASP:Panel with the "visible" property set to false and toggle that value based on the input.
Why not use different files instead? redirect to different pages. That would avoid having to have if statements everywhere.
OR
put your data in panels and just hide one or the other panel1.visible = (true/false). That's the best thing to do if you have to have it all in the same aspx page.
I prefer doing it on the ASPX page using DataBinding:
<asp:PlaceHolder runat="server" ID="Messages">
<asp:Label runat="server" Visible=<%# Request.QueryString("page") = 1 %> Text="Message 1" />
<asp:Label runat="server" Visible=<%# Request.QueryString("page") <> 1 %> Text="Message 2"/>
</asp:PlaceHolder>
Then on the server side:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
Messages.DataBind()
End Sub
For future reference, you can still use the classic ASP way to control content. Here's an ASPX page I wrote just now:
<%# Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<%
if (3 == 9)
{%>
<span>Hello</span>
<%
}
else
{
%> <span>What?</span > <%
}
%>
</div>
</form>
</body>
</html>
When the page renders, it displays 'What?' on the page.
However, I would say that this is bad practise and poor design! Use either womp's suggestion of a multiview, or a page redirect.