I have a menu of report links in my master page. I need to append an ID to the end of each whenever the user changes a value on the child page. What's a good way to accomplish this?
UPDATE: I should have mentioned that the child update is happening inside an UpdatePanel, meaning the master page is not reloaded when the change happens.
A MasterPage is really a child control of the page which it controls. You can control a MasterPage like any other control on your page (almost). All you need to do is get a reference to it.
You add a property to the code of your MasterPage, so its code may look something like this:
public partial class _default : System.Web.UI.MasterPage
{
protected string m_myString = string.Empty;
public string myString
{
get { return m_myString; }
set { m_myString = value; }
}
protected void Page_Load(object sender, EventArgs e)
{
}
}
Then you have to cast the this.Master property to your MasterPage
public partial class index : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
// Cast here to get access to your MasterPage
_default x = (_default)this.Master;
x.myString = "foo";
}
}
In response to your UPDATE:
The updated panel could write the ID to a hidden field and the menu events could look for that hidden fields in Request.Form["fieldName"].
Note that you shouldn't fieldName.Text because ASP.NET does a bad job of returning the right value for fields that have been AJAXed.
Related
I have a user control on the master page and I would like to pass in a value into that user control from the subpage, how would I be able to pass the values?
This control is in the master page
<%# Register TagPrefix="test" TagName="Data" Src="controls/TEST.ascx" %>
This code variable is within the user control
public partial class Controls_TEST : System.Web.UI.UserControl
{
private string _Title;
public string Title
{
get { return _Title; }
set { _Title = value; }
}
}
Code within the subpage
public partial class sub_page : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Controls_Test m = LoadControl("~/Controls/TEST.ascx");
m.Title = "TEST";
}
}
Note the sample code within subpage does not work because it cannot find that user control within the subpage.
I've tried Page.Master.FindControl and it also does not work for me. PLease help.
Use properties to communicate from your Page to your MasterPage and use properties to communicate from your MasterPage to the UserControl.
To get a reference to the control in your MasterPage you should provide a public property that returns it:
For example(in MasterPage):
public Controls_Test MyControl
{
get
{
return Controls_TEST1;
}
}
And you can call this property from one of your ContentPages in this way(f.e. if your master's type is named "SiteMaster"):
protected void Page_Load(object sender, EventArgs e)
{
((SiteMaster)Page.Master).MyControl.Title = "TEST";
}
As a rule of thumb: the more you encapsulate your controls, the more robust ,failsafe, maintanable and extendable your code will be.
Hence it would be better to provide only access to the Title rather than to the whole UserControl.
In MasterPage:
public String Title
{
get
{
return Controls_TEST1.Title;
}
set
{
Controls_TEST1.Title = value;
}
}
In the ContentPage:
((SiteMaster)Page.Master).Title = "TEST";
On this way you could change the logic and controls in your UserControl and MasterPage without having problems in your pages that already have accessed the UserControl directly.
I want to build a server control that inherits from System.Web.UI.WebControls.MultiView.
The control will contain a collection of server controls that inherit from System.Web.UI.WebControls.View in turn. However, when I add a single view to the control's View collection, nothing gets rendered...
public class WizardMultiview : System.Web.UI.WebControls.MultiView
{
// field
private WizardStart _start;
override CreateChildControls()
{
this._start = new WizardStart(); // custom view
this._start.ID = "WizardStart1";
this.Views.Add(this._start);
this.ActiveViewIndex = 0;
}
override Render(HtmlTextWriter writer)
{
// NOTE: at this point the control can't render itself.
}
}
Then, within the Default.aspx.cs I do:
public void Page_Load(object sender, EventArgs e)
{
My.Controls.WizardMultiview view = new My.Controls.WizardMultiview();
this.Panel1.Controls.Add(view); // this is a Panel on the Default.aspx page
}
The custom View control looks like this:
public class WizardStart : System.Web.UI.WebControls.View
{
override Render(HtmlTextWriter writer)
{
writer.WriteLine("I am the starting point");
}
}
When I add this control an ASPX page, nothing happens. But if I create a MultiView, and add the MultiView to a CompositeControl's Control Collection and add the view to this MultiView, it works fine? I'm sure what I want to achieve is possible?
I have the following that I'm using in every page:
public partial class Pages_MyPage : System.Web.UI.Page
{
ViewUserPreferencesModel TheUserPreferences;
Protected void Page_Load(object sender, EventArgs e)
{
TheUserPreferences = (ViewUserPreferencesModel)Session["SessionUserPreferences"];
And then I use a Page Method like this:
[WebMethod]
public static string GetAppointements(string DateInput)
{
ViewUserPreferencesModel TheUserPreferences = (ViewUserPreferencesModel)HttpContext.Current.Session["SessionUserPreferences"];
My question is this: Do I need to include the statement that loads user preferences when I run the page method or are the statements in the Page_Load event triggered when the page method is called, and if they are, will the variable be populated?
Thanks.
No, Page Methods do not follow the ASP.NET page lifecycle. However, even if they did, your TheUserPreferences variable won't be accessible in the static context.
Here is my master page code behind:
namespace mysite.MasterPages
{
public partial class Main : System.Web.UI.MasterPage
{
public bool isLoggedIn;
protected void Page_Load(object sender, EventArgs e)
{
isLoggedIn = Request.IsAuthenticated; // Is the user currently logged in
}
}
}
Here is my register page code behind:
namespace mysite
{
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (((MasterPage)Page.Master).isLoggedIn)
{
Response.Redirect("default.aspx");
}
}
}
}
I'm trying to make the isloggedIn accessible to all pages using that as a master page! I get errors like:
Error 2 The name 'isLoggedIn' does not exist in the current context
Error 3 'System.Web.UI.MasterPage' does not contain a definition for 'isLoggedIn' and no extension method 'isLoggedIn' accepting a first argument of type 'System.Web.UI.MasterPage' could be found (are you missing a using directive or an assembly reference?)
Any help appreciated.
add <%# MasterType VirtualPath="~/Main.master" %> to your page markup.
and your this.Master's type becomes AlphaPack.MasterPages.Main instead of System.Web.UI.MasterPage. So you will be able to access it without cast:
this.Master.IsLoggednIn
Currently you need do next:
((AlphaPack.MasterPages.Main)this.Master).isLoggednIn
And better - create a property. And hold data not in variable but in ViewState (read Control State vs. View State):
namespace AlphaPack.MasterPages
{
public partial class Main : System.Web.UI.MasterPage
{
protected void Page_Load(object sender, EventArgs e)
{
this.IsLoggedIn = Request.IsAuthenticated;
}
public bool IsLoggedIn
{
get { return this.ViewState["isLoggedIn"] as bool? ?? false; }
set { this.ViewState["isLoggedIn"] = value; }
}
}
}
And what about code-behind. I recommend to use Web App project, not Web Site project (which is out-of-date)!
Next markup syntax is used. Web app:
<%# Page Language="C#" AutoEventWireup="true" CodeBehind="MyPage.aspx.cs" Inherits="MyNamespace.MyPage" MasterPageFile="~/MyMaster.master" Title="MyTitile" %>
and web site:
<%# Page Language="C#" AutoEventWireup="true" CodeFile="MyPage.aspx.cs" Inherits="MyPage" MasterPageFile="~/MyMaster.master" Title="MyTitile" %>
if (((MasterPage)Page.Master).isLoggedIn)
Should be
if (((mysite.MasterPages.Main)Page.Master).isLoggedIn)
You cast Master to a MasterPage type (which is useless as it is already a MasterPage). But MasterPage doesn't contain the property isLoggedIn. That's why you can't access it.
So, just cast the Master property to the right type, in your case mysite.MasterPages.Main
The problem here is that your are declaring isLoggedIn within an inline code-block, so it will only be scoped to within that block.
You'll need to add it as a variable within the code-behind class or within <script runat="server"></script> tags, if adding the server-side code inline, i.e. (trimmed down for brevity):
<script runat="server">
public bool IsLoggedIn;
protected void Page_Load(object sender, EventArgs e)
{
IsLoggedIn = Request.IsAuthenticated;
}
</script>
You could then access the master page in subpages like so:
<%
if (((MasterPage)Page.Master).IsLoggedIn)
{
}
%>
However, I'm not sure that this is the best way to achieve what you want. I would probably take that logic out of the master page and stick it in a purpose built authentication class or service.
Usually one would store such Global 'states' inside a session variable. Are passing it around as a query string parameter?
And why are you not putting the code in the code behind?
Edit 1:
Just move this logic:
Response.Redirect("default.aspx");
directly into your masterpage:
protected void Page_Load(object sender, EventArgs e)
{
if (Request.IsAuthenticated) // Is the user currently logged in
{
Response.Redirect("default.aspx");
}
}
If this is the default behaviour you want for all pages that will be using this Master Page.
Edit 2:
you said in a comment :
and how would i go about accessing the
variable on other pages?
There are 3 ways I can think of:
Query String (Per Page Request)
ViewState (Per Page)
Session Variable (Available Globally)
Let's say I have a custom control that looks like this
<cc:MyControl runat="server" ID="myc" LinkControlID="NewParent" />
and, on the same page:
<asp:TextBox runat="server" ID="NewParent" />
What I would like to do is, from MyControl, change NewParent's parent so that it would be part of MyControl's Controls collection. When I try to do this, from OnInit, I get:
The control collection cannot be modified during DataBind, Init, Load, PreRender or Unload phases.
Which makes sense, but is there a way around this? I'm OK if NewParent remains the child of the Page as long as from MyControl I can somehow redirect the rendering to MyControl's control.
Can this be done? Thanks.
EDIT:
To clarify here's a mockup of MyControl:
public class MyControl : Panel
{
protected override void OnInit(System.EventArgs e)
{
base.OnInit(e);
if (!String.IsNullOrEmpty(LinkControlID))
{
Control link = Parent.FindControl(LinkControlID);
if (link != null)
{
Controls.Add(link);
}
}
}
public string LinkControlID { get; set; }
}
This assumes that MyControl and LinkControlID are placed on the same level in the tree hierarchy, which is OK in my case.
why don't you try adding it in Page_LoadComplete
myc.Controls.Add(NewParent);
I couldn't reproduce it, but as aman.tur suggested, have you tried another event? Overriding CreateChildControls() seems like the right place for it.
#TheVillageIdiot's suggestion worked for me:
protected void Page_Init(object sender, EventArgs e)
{
Page.LoadComplete += Page_LoadComplete;
}
private void Page_LoadComplete(object sender, EventArgs e)
{
if (InHeader)
{
Page.Header.Controls.Add(this);
}
}
Mind you, I had different requirements, but I don't think it should be much of an issue if you can access the new parent control from within your MyControl. The general format is to add an event listener on the Page to make changes on LoadComplete.