ASPX - Reading master page element returns null - asp.net

I have an anchor link in the master page and trying to assign its href in code behind, but the element is null.
Default.master
<body>
<header>
<asp:Hyperlink ID="ancLogout" runat="Server" Text="Logout" />
</header>
</body>
Default.master.cs
protected void Page_Load(object sender, EventArgs e)
{
if (ancLogout != null)
{
ancLogout.NavigateUrl = String.Format("{0}?logout=1", HttpContext.Current.Request.Url.AbsoluteUri);
}
}
The ancLogout is always null.

have just tried your exact code and theres no issues for me? ... maybe a lower case 'S' on server but shouldn't matter

Related

asp:Button - onclick event fires code on a different code-behind?

I'm teaching myself to use a site.master page with child webforms embedded using the ContentPlaceHolderID object. I'm figuring it out, but I have one question; is it possible to put a button on the site.master page that fires code on the codebehind pages of the child forms? If I can do that, it will really simplify what I'm trying to accomplish.
I tried to 'inherit' both codebehinds, but of course that didn't work. Is there a way to do this?
Yes there is a way to do this. You need to set UseSubmitBehavior button property to false and then you can access the control that causes the post back using Request.Params.Get("__EVENTTARGET"); So the code would look like this:
Button definition in Site.Master markup:
<asp:Button ID="MyButton" runat="server" Text="Button" UseSubmitBehavior="false" />
code behind within any inherited page:
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
// in case you have code to be executed on first load
}
else
{
string myButtonCtrl = Request.Params.Get("__EVENTTARGET");
if (myButtonCtrl != null && myButtonCtrl.EndsWith("MyButton"))
{
// MyButton has been clicked!
}
}
}

Add a HtmlGenericControl to master page from server code

I'm creating a website which allows users to log in. After logging in successfully, user's name should be displayed across each page, for example, at the top right corner. I have a ContentPlaceHolder on Master Page. An h3 tag would then be created and added into this ContentPlaceHolder.
Master Page:
<asp:ContentPlaceHolder runat="server" ID="UserNamePlaceHolder">
</asp:ContentPlaceHolder>
Login Page:
<%# MasterType VirtualPath="~/Master" %>
Login Class:
protected void Login_LoggedIn(object sender, EventArgs e)
{
ContentPlaceHolder userNamePlaceHolder =
(ContentPlaceHolder)Master.FindControl("UserNamePlaceHolder");
var h3 = new HtmlGenericControl("h3");
h3.InnerHtml = login.UserName;
userNamePlaceHolder.Controls.Add(h3);
}
I did debugging step by step. Nothing went wrong: no null or empty value, each variable was created. However, the user name was not displayed at all. Does anyone have an idea?
A cleaner and better approach would be to create a public property on the Master page:
public string UserName
{
get
{
return Literal1.Text;
}
set
{
Literal1.Text = value;
}
}
That's it place the literal with ID Literal1 anywhere you want on the master page:
<asp:Literal runat="server" ID="Literal1" />
You are already adding Master directive for strongly typing Master class, so now your login class would look like this:
protected void Login_LoggedIn(object sender, EventArgs e)
{
Master.UserName = login.UserName;
userNamePlaceHolder.Controls.Add(h3);
}
Hope this helps.

cannot access hiddenfield value in masterpage on page_load event from child page

I'm trying to access a hiddenfield value from my masterpage that is set in my child aspx page, but cannot access it the masterpage codebehind page_load event.
Child aspx page:
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="Server">
<telerik:RadStyleSheetManager ID="RadStyleSheetManager1" runat="server">
</telerik:RadStyleSheetManager>
<div class="center_content">
<div style="text-align: left">
<h2>
</h2>
</div>
<div style="text-align: left">
<uc1:Chart ID="Chart1" runat="server" />
</div>
</div>
<asp:HiddenField ID="hid1" runat="server" Value="Satellite Availability % Report" />
Master page:
<asp:Label runat="server" ID="Label1" Style="text-align: right; font-size: xx-large; color: #808080"></asp:Label>
Master page code behind: This is where I want to set the text value of the report from the child page.
protected void Page_Load(object sender, EventArgs e)
{
HiddenField hid1 = (HiddenField)MainContent.FindControl("MainContent_hid1");
if (hid1 != null)
{
Label1.Text = hid1.Value;
} }
<input type="hidden" name="ctl00$MainContent$hdnRptTitle" id="MainContent_hdnRptTitle" value="Satellite Availability % Report" />
There is no intellisense for the hdnRptTitle variable.
How can I get this to work? It seems simple enough, but don't know why it not working...
You can add the below code in your MasterPage:
HiddenField hid1 = (HiddenField)MainContent.FindControl("hid1");
if (hid1 != null)
{
Label1.Text = hid1.Value;
}
EDIT: Make sure your Label on the MasterPage is outside your ContentPlaceHolder, as I made this mistake when I first tested.
The above code should work as provided, with your control names, I'm not sure why you are using:
.FindControl("MainContent_hid1");
instead of
.FindControl("hid1");
You can use like this.
There can be multiple conterntPlaceHolder on your master page.
use the id which contains your hidden field in this case I assume that it is ContentPlaceHolder1
HiddenField hid1 = (HiddenField)ContentPlaceHolder1.FindControl("hdnRptTitle");
if (hid1 != null)
{
Label1.Text = hid1.Value;
}
There is a similar post on so
How to access content page controls from master page in asp.net
You can reference a master page and get the control like this:
VB.Net:
Dim te As HiddenField
Dim val As String
te = Me.Page.Master.FindControl("hdnRptTitle")
val = te.Value
c#:
HiddenField te = default(HiddenField);
string val = null;
te = this.Page.Master.FindControl("hdnRptTitle");
val = te.Value;
Why do you think that you can access a control in a content-page of a master-page? A MasterPage is used for multiple pages, why do you want to hardlink it with a specific page, it won't work anymore without it. If the HiddenField is essential for the operation of the master you should declare it there.
For every child page, there is a different rpt title which needs to
show up on the master page. How can I accomplish this?
Then the content page can access it's master to set the text but not vice-versa.
You could provide a public property in the master, e.g.:
public string ReportTitle
{
get { return this.LblReportTitle.Text; }
set { this.LblReportTitle.Text = value; }
}
and in the ContentPage, for example in it's Page_Load:
protected void Page_Load(object sender, EventArgs e)
{
// assuming the type of your master is SiteMaster
var master = this.Master as SiteMaster;
if (master != null)
master.ReportTitle = hdnRptTitle.Value;
}
This approach is still linking the master with one (or multiple) of it's childs, but it would still "work" if the content-page would use a different master-type. You'd also be informed with a compiler error if somebody remove or change the property.
However, where the content stores the report-type or where the master displays it is an implementation detail and can be changed in future without breaking anything.

(ModalPopupExtender) two components with the same id can't be added to the application

I have a user control which I add on a page whenever user click on button. Following is the code to add control.
protected void Page_Init(object sender, EventArgs e)
{
if (Session["ControlCount"] != null)
{
for (int i = 1; i <= (int)Session["ControlCount"]; i++)
{
Control myUserControl = LoadControl("~/Controls/MessageControl.ascx");
divMessageControl.Controls.Add(myUserControl);
}
}
}
protected void Page_Load(object sender, EventArgs e)
{
}
protected void btnExpand_Click(object sender, EventArgs e)
{
int count = 0;
if (Session["ControlCount"] != null)
{
count = Convert.ToInt32(Session["ControlCount"]);
}
Control myUserControl = (Control)Page.LoadControl("~/Controls/MessageControl.ascx");
divMessageControl.Controls.Add(myUserControl);
Session["ControlCount"] = count + 1;
}
This control has ModalPopupExtender popup. When I add 2nd control on page it throws an error internally which i can see in firebug. How to make this popup id unique?
<asp:ModalPopupExtender ID="mpeReply" BehaviorID="mpeReply" runat="server" TargetControlID="btnReply"
PopupControlID="pnlReply" BackgroundCssClass="ModalPopupBG1">
</asp:ModalPopupExtender>
Sys.InvalidOperationException: Sys.InvalidOperationException: Two
components with the same id 'mpeReply' can't be added to the
application.
I have found the solution to this problem, as much as a lot of people have said, the simple solution is that your HTML is not properly formed - there is either an extra or missing closing tag to an element. Make sure that all your tags are properly closed and the problem should go away - struggled all day with this one!
I used this code to fix my problem, notice the ScriptMode is set to "Release"
<AjaxControlToolkit:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server" ScriptMode="Release">
</AjaxControlToolkit:ToolkitScriptManager>
I see a similar answer from this link:
http://www.advancesharp.com/questions/17658/sys-invalidoperationexception-two-components-with-the-same-id-xxx-can-t-be-added-to-the-application
Remove BehaviorID property from extender
Similar issue here. The solution for me was to change the Script Manager from a shortcut close tag to the full close tag , after adding the ScriptMode="Release" attribute:
Change:
<asp:ScriptManager ID="ScriptManager1" ScriptMode="Release" runat="server" />
to:
<asp:ScriptManager ID="ScriptManager1" ScriptMode="Release" runat="server></asp:ScriptManager>

html button elemenents and onserverclick attribute in asp.net

I have been experiencing some very strange behavior using html buttons with the onserverclick attribute. What I am trying to do is use jQuery to designate the default button on the page. By default button I mean the button that is "clicked" when a user hits enter. In testing, I would hit enter while in an input field and sometimes the intended "default" button was clicked and the server side method defined in the corresponding onserverclick attribute was hit. Other times a post back was made without hitting the server method. In order to isolate the issue I created a minimal test case and found some very interesting results.
client side:
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Untitled Page</title>
<script type="text/javascript" src="/scripts/jquery-1.4.min.js"></script>
</head>
<body>
<form id="form1" runat="server">
<asp:Label ID="_response" runat="server"></asp:Label>
<input id="input1" type="text" />
<input id="input2" type="text" />
<button id="first" type="button" class="defaultBtn" runat="server" onserverclick="ServerMethod1">test1</button>
<button id="second" type="button" runat="server" onserverclick="ServerMethod2">test2</button>
</form>
<script type="text/javascript">
jQuery('form input').keyup(
function(e) {
if ((e.which && e.which == 13) || (e.keyCode && e.keyCode == 13)) {
$('button.defaultBtn').click();
return true;
}
}
);
</script>
</body>
</html>
server side:
public partial class admin_spikes_ButtonSubmitTest : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void ServerMethod1(object sender, EventArgs e)
{
_response.Text = "server method1 was hit";
}
protected void ServerMethod2(object sender, EventArgs e)
{
_response.Text = "server method2 was hit";
}
}
What I found was that everything worked as expected with this code except when I removed one of the input elements. In Firefox 3.6 and IE 8 when only one input exists on the page, hitting enter does not trigger the onserverclick, it makes a post back without even being jQuery "clicked" or actually "clicked". You can test this by starting with two inputs and clicking "test2". This will output "server method2 was hit". Then just hit enter and the output will be "server method1 was hit. Now take away an input and run the same test. Click "test2" see the results, then hit enter and you will see that nothing will change because the "test1" method was never hit. Does anyone know what is going on?
Thanks
p.s. Chrome worked as expected
Try this:
jQuery('form input').keyup(
function(e) {
if ((e.which && e.which == 13) || (e.keyCode && e.keyCode == 13)) {
$('#__EVENTTARGET').val($('.defaultBtn').attr('name') );
document.forms[0].submit();
return true;
}
}
);
Or you may use the DefaultButton form's attribute:
<asp:Form runat="server" id="form1" DefaultButton="first">
...
</asp:Form>

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