Develop Reference

Get Master Page Control Value In Content Page static webmethod in c#

I can fetch MasterPage control value in Content Page
but I can't understand how to fetch MasterPage control value in Content Page in static webmethod
on google, I found many interesting articles but all of them use ajax and jquery technology
but ajax and jquery is not suitable for me in this case
any suggestions, please?
my code below
masterpage
public partial class MasterPage : MasterPage
{
public string UserNamePropertyOnMasterPage
{
get
{
// Get value of control on master page
return lblUserName.Text;
}
set
{
// Set new value for control on master page
lblUserName.Text = value;
}
}
}
<form id="form1" runat="server">
<div>
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">
</asp:ContentPlaceHolder>
<span style="font-size: 25px; background-color: greenyellow">
<asp:Label ID="lblUserName" runat="server" Text="Shazam"></asp:Label>
</span>
</form>
code-behind of Default.aspx.cs
public partial class _Default : Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
lblCurrentUserName.Font.Size = 20;
lblCurrentUserName.BackColor = Color.Yellow;
lblCurrentUserName.Text = "Value Received in Content Page : " + Master.UserNamePropertyOnMasterPage;
}
}
[WebMethod(EnableSession = true)]
[ScriptMethod]
public static void SetLabel(string UserNamePropertyOnMasterPage)
{
HttpContext.Current.Response.Cache.SetExpires(DateTime.UtcNow.AddMinutes(-1));
HttpContext.Current.Response.Cache.SetCacheability(HttpCacheability.NoCache);
HttpContext.Current.Response.Cache.SetNoStore();
Label Hname = (Label)Master.UserNamePropertyOnMasterPage;
lblCurrentUserName.Text = Hname;
}
}
markup of Default.aspx
<%# Page Title="" Language="C#" MasterPageFile="MasterPage.master"
AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<%# MasterType VirtualPath="MasterPage.master" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<asp:Label ID="lblCurrentUserName" runat="server" Text=""></asp:Label>
</asp:Content>

It is not possible to call a master page method from a static web method. This is a fundamental concept to understand in C#. Basically the master page does not exist during the web request. Only the web method is called.
Use JavaScript/jQuery to update the current page HTML.

ASP how to find controls of type on a child page of a master page

I have a master page master.page.
And I have a child page default.aspx that inheirts master.
How do I preform the following and actually find controls. In the below code I never find my panels.
codebehind - content-page
foreach (Panel pnl in this.Page.Controls.OfType<Panel>())
{
if (pnl.ID.ToUpper() == texthi.ToUpper().Replace(" ", ""))
{
pnl.Visible = true;
}
else
{
pnl.Visible = false;
}
}
aspx - content-page
<%# Page Title="" Language="C#" MasterPageFile="~/secure/Wizard.master" AutoEventWireup="true"
CodeFile="AddWarranty.aspx.cs" Inherits="secure_Warranties_AddWarranty" %>
<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder_NavigationPanel"
runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<asp:ScriptManager runat="server" ID="sm1">
</asp:ScriptManager>
<div id="header">
<p id="layoutdims">
</p>
</div>
<div class="colmask leftmenu">
<div class="colleft">
<div class="col1">
<asp:Panel runat="server" ID="VehicleInformation" Visible="true">
<legend>VEHICLE INFORMATION</legend>
</asp:Panel>
<asp:Panel runat="server" ID="CustomerInformation" Visible="false">
<legend>CUSTOMER INFORMATION</legend>
</asp:Panel>
</div>

The reason is that Enumerable.TypeOf does not look recursivelsy into child controls but only the top-container. Since you're using it on the page's ControlCollection you'll find only panels which are sitting on the top of the page. But your panels are inside of other divs.
Make the parent div(with class="col1") runat=server(or use Panel) and access it in codebehind:
foreach (Panel pnl in div.Controls.OfType<Panel>())
{
// ...
}

How to execute javascript pageload event on multi instance web user control

I'm developing an web user control for that i need to set some properties at page load (client side page load). My control works fine with one instance on page.
But when i need multiple instance of that control on same page.Page load event shows effects only on last control.
My control
<%# Control Language="C#" AutoEventWireup="true" CodeFile="WebUserControlLoadTest.ascx.cs" Inherits="WebUserControlLoadTest" ClientIDMode="Predictable" %>
<link rel="stylesheet" href="GridViewCSSThemes/YahooGridView.css" type="text/css" media="screen" />
<script runat="server" type="text/C#">
static Int16 _count;
public static Int16 count
{
get { return _count++; }
}
</script>
<script type="text/javascript">
function pageLoad() {
document.getElementById('<%= Hidden_RowIndex.ClientID%>').value = '<%= count%>';
document.getElementById('<%= txtUC.ClientID%>').value = "Count : " + document.getElementById('<%= Hidden_RowIndex.ClientID%>').value;
}
</script>
<asp:HiddenField ID="Hidden_RowIndex" Value="" runat="server" />
<asp:TextBox ID="txtUC" CssClass="tb10" Enabled="false" runat="server"></asp:TextBox>
Use control on aspx page
<%# Page Language="C#" AutoEventWireup="true" CodeFile="ContextMenuTest.aspx.cs" Inherits="ContextMenuTest" %>
<%# Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %>
<%# Register TagPrefix="uc1" TagName="UCTest" Src="~/WebUserControlLoadTest.ascx" %>
<!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>Java Script Load Test</title>
</head>
<body>
<form id="form1" runat="server">
<ajaxToolkit:ToolkitScriptManager runat="server" ID="ScriptManager1" EnablePageMethods="true" />
<table style="padding:1%;width:100%;">
<tr>
<td>
<uc1:UCTest runat="server" ID="UCTest1"/>
</td>
</tr>
<tr>
<td>
<uc1:UCTest runat="server" ID="UCTest2"/>
</td>
</tr>
</table>
</form>
</body>
After execution result will be Count - 0 in first Control and Count - 1 in Second.
But it shows 1 Control blank and second with Control -1 text.
Can any one tell me how can i make different instance of java-script page-load event in multi instance web user control.

The problem is
static Int16 _count;
public static Int16 count
{
get { return _count++; }
}
If you declare your control multiple times, then you override the counter each time the control is rendered.
You need a smarter Javascript, for examle, add a class on the control wrapper inside WebUserControlLoadTest.ascx something like
<div class="myControl">
<asp:HiddenField ID="Hidden_RowIndex" Value="" runat="server" />
<asp:TextBox ID="txtUC" CssClass="tb10" Enabled="false" runat="server">
</asp:TextBox>
</div>
and at the top of the aspx page you can have this:
$(document).ready(function(){
var count = 0;
$("myControl input:hidden").each(function(){$(this).value = count++});
});

Access child page controls from base page

Inside my ASP.NET application all my web content pages are derived from a base class which is derived from System.Web.UI.Page. Inside this base class I need to get some controls found in one derived class, SamplePage.aspx : BaseClass.cs. It I add the C# code below on Page Load inside SamplePage.aspx it finds the ContentPlaceHolderControl,
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">
</asp:ContentPlaceHolder> /* defined in the master page */
/* inside SamplePage.aspx */
<ajaxtoolkit:tabcontainer runat="server" id="tabsmain" height="405px" Width="625px">
ContentPlaceHolder cph = (ContentPlaceHolder)this.Master.FindControl("ContentPlaceHolder1");
AjaxControlToolkit.TabContainer container = (AjaxControlToolkit.TabContainer)cph.FindControl("tabsmain");
whereas if I add it inside the base class I get this error:
Content controls have to be top-level controls in a content page or a nested master page that references a master page.
Is there a way I can get the ContentPlaceHolder inside my base class too? And how can I access it?

Here is complete sample code how you can access ContentPlaceHolder:
First master code (Site1.master):
<%# Master Language="C#" AutoEventWireup="true" CodeBehind="Site1.master.cs" Inherits="WebTesterInherit.Site1" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<asp:ContentPlaceHolder ID="head" runat="server">
</asp:ContentPlaceHolder>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">
</asp:ContentPlaceHolder>
</div>
</form>
</body>
</html>
Now custom class that inherits from Page:
public class MyPage: System.Web.UI.Page
{
public System.Web.UI.WebControls.ContentPlaceHolder GetMyContentPlaceHolder()
{
System.Web.UI.WebControls.ContentPlaceHolder holder = null;
Site1 site = this.Master as Site1;
if (site != null)
{
holder = site.FindControl("ContentPlaceHolder1") as System.Web.UI.WebControls.ContentPlaceHolder;
}
return holder;
}
}
And finally page that inherits from MyPage (Default.aspx):
<%# Page Title="" Language="C#" MasterPageFile="~/Site1.Master" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebTesterInherit.Default" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
<asp:Button ID="btnTest" runat="server" Text="Test" OnClick="btnTest_Click"/><br />
<asp:Label ID="lblMessage" runat="server" Text=""></asp:Label>
</asp:Content>
Code for Default.aspx:
public partial class Default : MyPage
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void btnTest_Click(object sender, EventArgs e)
{
try
{
System.Web.UI.WebControls.ContentPlaceHolder holder = base.GetMyContentPlaceHolder();
lblMessage.Text = string.Format("Holder contains {0} control(s).", holder.Controls.Count);
}
catch (Exception ex)
{
lblMessage.Text = string.Format("Error: {0}", ex.Message);
}
}
}

I've checked and you can find a control nested in ContentPlaceHolder from base class OnLoad method.
Sure it can be done... but remember that some pages may have different controls in theirs CPH. Are you sure that you are in the context of a page which actually has tabsmain control?
I think if you have to do such things you have some design problem. A mix of master page and downward FindControl (base class -> derived class) just doesn't feel right.

Universal "search by id and type" method:
protected T GetControlOfType<T>(Control root, string id) where T : Control {
var stack = new Stack<Control>();
stack.Push(root);
while (stack.Count > 0) {
var control = stack.Pop();
var typedControl = control as T;
if (typedControl != null && string.Compare(id, typedControl.ID, StringComparison.Ordinal) == 0) {
return typedControl;
}
foreach (Control child in control.Controls) {
stack.Push(child);
}
}
return default(T);
}
Usage:
var control = GetControlOfType<MyControl>(Page, "MyControlServerID");

Affect another document on submit

I've got a upload function that pops up in a diffrent window, when i've submitted i want to send infomation back to the page that the upload window opened from.
Is that possible some way with ASP.net or C#?
Or would i have to use some javascript ? and how?
My 2 pages:
news.aspx - Contains a formview with my news. and a form with some inputs in.
This is where the link to open the upload page is...
uploader.aspx - Contains my upload controller and C# code to upload.
This should send a string from my C# code back to news.aspx and put it in one of my input fields or a label, not important.
uploader.aspx file:
<form id="form1" runat="server">
<div>
Vælg en fil at uploade:<br />
<asp:FileUpLoad id="FileUpLoad1" runat="server" />
<asp:Button id="UploadBtn" Text="Upload File" OnClick="UploadBtn_Click" runat="server" Width="105px" />
<br />
<asp:Label ID="Label1" runat="server" Text=""></asp:Label>
</div>
</form>
Behind Code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class admin_Default2 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void UploadBtn_Click(object sender, EventArgs e) {
Label1.Text = "Status: Uploader...";
if (FileUpLoad1.HasFile) {
FileUpLoad1.SaveAs(#"C:\Users\138409\Documents\Visual Studio 2010\Projects\Musicon\img\news\" + FileUpLoad1.FileName);
Label1.Text = "Status: " + FileUpLoad1.FileName + " er blevet uploadet";
} else {
Label1.Text = "Status: Filen blev ikke uploadet...";
}
}
}

Here is some Javascript code to create a popup window and, before the popup window closes, retrieve some information. (I will add a jQuery example in a bit)
//Site1.Master
<%# Master Language="C#" AutoEventWireup="true" CodeBehind="Site1.master.cs" Inherits="PopupRedirect.Site1" %>
<!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>
<asp:ContentPlaceHolder ID="head" runat="server">
</asp:ContentPlaceHolder>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">
</asp:ContentPlaceHolder>
</div>
</form>
</body>
</html>
//Page1.aspx
<%# Page Title="" Language="C#" MasterPageFile="Site1.Master" AutoEventWireup="true" CodeBehind="Page1.aspx.cs" Inherits="PopupRedirect.Page1" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
<script type="text/javascript">
var message = "Hello World!";
var closeWindow = function(event) {
event.preventDefault();
window.close();
};
window.onload = function() {
document.getElementById('upload').addEventListener('click', closeWindow, false);
};
</script>
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
<button id="upload">Upload File</button>
</asp:Content>
//UploadPage.aspx
<%# Page Title="" Language="C#" MasterPageFile="Site1.Master" AutoEventWireup="true" CodeBehind="UploadPage.aspx.cs" Inherits="PopupRedirect.UploadPage" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
<script type="text/javascript">
var popupWindow;
var windowOptions = "menubar=yes,location=yes,resizable=no,scrollbars=no,status=yes,width=350,height=350";
var upload = function (event) {
event.preventDefault();
popupWindow = window.open("Page1.aspx", "Upload Page", windowOptions);
popupWindow.onbeforeunload = pageClose;
};
var pageLoad = function(event) {
document.getElementById('uploadLink').addEventListener('click', upload, false);
};
var pageClose = function (event) {
//put the code here that you want to execute when the window is done.
//like getting the value of some javascript variables
if(typeof (popupWindow.message) != "undefined") {
alert(popupWindow.message);
}
};
window.onload = pageLoad;
</script>
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
<span>Welcome to this page! Click to upload.</span>
<button id="uploadLink">Upload</button>
</asp:Content>