Programmatic Accessing A Control From Base To Derived?
Nov 15, 2010
In a recent post, I expressed a need to access the properties for the body using declarative syntax, see
Contentplaceholder for replacing attributes?
But, the syntax confuses the editor which is not acceptable.
My hypothesis for a workable solution is to make the change in code. To derive a class from System.Web.UI.Page with extended functionality. However, I want for the designer to be able to still use declarative syntax to set the body tag.
I do not want to have to change any code in my aspx web pages except that they derive from base I want to be able to set these properties using declarative syntax, merely by adding a tag in the derived page I'm not immediately sure how to go about doing this because it doesn't exactly fit the OOP paradigm and I'm not sure where the changes need to be made.
I can use a findcontrol in the base to see if the placeholder has been added. But, not sure exactly at what point in the page processing lifecycle that I can use this findcontrol. I need to set the body before it renders but also be able to grab something from the declarative code.
Is it possible for a derived controls to inherit his base control skin.
Say I am deriving a control from TextBox, is it possible for the derived control to inherit the skin settings for Textbox or do they need to be defined again?
I am applying the default skins to all controls through the styleSheetTheme Page property I am using the Devexpress asp.net controls if that makes any difference.
Since we can access the private data member of base class in the derived class with the help of friend function. How can we do the same in C# asp.net? I mean whats the alternative of friend function in C# asp.net
I don't know if this has to do with how FindControl works or how scope works. But my base class is having a hard time seeing the fields of child classes. Currently I'm planning have the derived class set a property in the base class, but there are a lot of derived classes, so that isn't a very attractive solution.
I have a class that derives from System.Web.UI.Page and have set my pages to derive from this custom page class instead of Page. At runtime, the controls are never initialized and throw a NullReferenceException. I've changed some class names and namespaces in the pasted code to protect the innocent. The only thing that I currently override in my PageBase is OnPreLoad and I do call the base.OnPreLoad. I'll eventually add more functionality to this PageBase but for now all that it has is this:
[Code]....
I've tried putting this into a class library (with System.Web referenced) and I've also tried moving the class into the web application and had the same results either way. As another strange twist, I have another class with derives from PageBase called IndexPageBase and it doesn't have this problem:
How do I create a new event in a base page class that fires after all derived pages have fired their load events but before any controls fire their load events.
The following code fires the event before the derived page's load event. I want it to fire the event after the derived page's load event but before all control load events:
Base Class:
Public Event FirstLoad(ByVal sender As Object, ByVal e As System.EventArgs) Private Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load If Not IsPostBack Then RaiseEvent FirstLoad(sender, e) End If End Sub
Derived Class:
Private Sub Page_FirstLoad(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.FirstLoad 'Stuff here happens before controls load but only on first page loads' End Sub
I'm overriding the OnActionExecuting method in a base Controller. When a form gets posted - anywhere, I want to check for a certain form element in this method. In any Controller method I can just include the FormCollection as one of the params in its signature, but if I try that with the OnActionExecuting method I get an error saying that there's no suitable method to override. How can I get past this?
i host my web site into a shared hosting and i need to set expiration header using iis but i didn't find my hosting allow this feature so , is there any way to set it into my web configuration or into my code ??
If there's a 0 in the field the code inserts a null. Otherwise it inserts a date. How can I change this to insert a NULL if a question mark "?" appears in the column?
This is what I tied using the OR operator but it's not working:
I would like to know how to add some additional child nodes to a custom user control class derived from System.Web.UI.Control. For example currently I have a control that contains no child nodes and on the design surface looks like the following.
What I am looking for is to have the ability to add n number of child nodes to this control from the design surface and then access their values from the code. So adding to the control stated above.
I'm accessing a Masterpage property from a regular page by doing the following:
[Code]....
I get the following error message:
Compiler Error Message: CS0246: The type or namespace name 'SecondMasterPage' could not be found (are you missing a using directive or an assembly reference?)
My base class file is a file called BaseClass.cs in my App_Code directory. Other functions in there work without errors. Why?
I have a application which uses webparts and 1 control is also a Script Control.So my user controls are derived from System.Web.UI.WebControls.WebParts.WebPart which makes them webpartsI have everything setup and working fine as far as the personalization and webpart goes... every thing displays and works fine.Except that 1 of my control needs to do a bit of work in the OnPreRender event and it turns out that event only gets fired when a user is loged in the application
my user controls are derived from System.Web.UI.WebControls.WebParts.WebPart which makes them webparts.I have everything setup and working fine as far as the personalization and webpart goes... every thing displays and works fine.Except that 1 of my control needs to do a bit of work in the OnPreRender event and it turns out that event only gets fired when a user is loged in the application.
Protected Overrides Sub OnPreRender(ByVal e As EventArgs) If Not Me.DesignMode Then Me.isloaded = True ' Test for ScriptManager and register if it exists sm = ScriptManager.GetCurrent(Page) [code]...
I have a custom basepage and a master page in my web application. In my master page, there are events that I run from each page in my web application. Instead of putting the code in each of my pages, I decided to create a base page that each web page will inherit from. Trouble is, I cannot get the base page to invoke the events on the master page.
I am new in asp .net.I am not able to undestand why we call base class method when we override methods/events.Like automatically visual studio will put base.OnInit() if you are overriding OnInit.
I have to implement User base security in my Web project using .Net3.5. Followings are some we need:
Roles can be Admin, Manage, Editor, Member etc User can have multiple roles Every roles has its own dynamic menus and restrictions/resources All menus and interface will populate dynamically from Database
I heard some where this kind of i.e user base security can be implemented using HashTable but I dont know how is it?
Today I came to know that for this kind of work Java people use Interceptor Design patterns. So, how could I do the same in asp.net C#?
I have a user control in silverlight which contains both XMAL and .cs file. But I wanna make it into a base control. In other word,I can make a control inherited it whose area in it can be edited. Just like Master Page in asp.net,you know. In the base control,I only have a lot of description in XMAL,perhaps it can be described in the .cs file,too.
The problem is that this inherited code is specific to the domain, and I want to eventually get the roles from the web.config file, so I can work on a VM not in the domain. have seen an example like this:
PrincipalPermission permCheck = new PrincipalPermission( null, @"DomainAdmin"); permCheck.Demand();
Since this throws an exception if user is not in role, how do I change this example to allow either of the two roles? I could use multiple IPrincipal.IsInRole() and then throw my own exception, but seems like there is probably a way to use the .Demand method with multiple roles. Update 12/21: Sample Code based on Union link from Ladislav's answer below:
PrincipalPermission ppAdmin = new PrincipalPermission(null, @"DomainAdmin"); PrincipalPermission ppAnother = new PrincipalPermission(null, @"DomainAnotherRole"); (ppAdmin.Union(ppAnother)).Demand();
I have a progress bar (which is a user control). When user, click a button, this progressbar will get displayed. The issue is ...even if the progressbar is visible, I am able to set focus to other controls in base page. I need to blur the base page...and set focus to user control.
I have a base user control (inherited from System.Web.UI.UserControl)
public delegate void MyEventHandler(object sender, MyEventArgs e); public event MyEventHandler ControlLoaded; //Fire the event from here protected override void OnLoad(EventArgs e) { MyEventArgs cmdEventArgs = new MyEventArgs("somearg"); ControlLoaded(this, cmdEventArgs); }
I have several controls that are derived from this base user control.
On the host ASPX page, I need to subscribe to the ControlLoaded event.
protected void Page_Load(object sender, EventArgs e) { //subscribe to the event //This line DOES NOT WORK as I cannot attach event to a base control - It needs an instance of the user control which I don't have BaseUserControl.ControlLoaded += new MyEventHandler(ControlLoaded); } private void ControlLoaded(object sender, MyEventArgs e) { // some control has been loaded }
I have this code that display a message when a button is click, but i am having more that one button on the form, how do i control the message base on the different button click.
I have a Web Forms app that uses forms authentication. I have a Crystal Reports Server 2008 V1 server with InfoView .NET installed and working. I have some Enterprise accounts setup. EDIT: I should mention that my Web Forms app is on a different server from Crystal Reports Server.
I need to know how to log on to InfoView .NET programmatically on my custom ASP .NET page (C#) and then transfer the user to InfoView without them having to type in the logon information.
Something like this would be nice (C#):
string username = "blah"; string password = "asdf"; // create logon token for crystal reports server // .. // this is the code I need Response.Redirect(url);
I did find this question, which gets me partway there, but it doesn't tell me how to pass the token to InfoView .NET. Some older docs also mention needing a cookie. I've also found other sites that show how to pass it to Java InfoView, but I need the .NET version.
I have advice that this might work for programmatically filling a set of literals from a set of object properties:-
[code]....
However, the line: ctl.Text = pageData.help(i).trim() fails because it's not understood that pageData.help(i) should translate to pageData.help1, pageData.help2, etc.
I am databinding a SqlDatasource to a GridView in 2 different ways.
1) Declaring the SqlDatasource in the .aspx page and setting the DatasourceID property on the GridView to its id
2) Creating the SqlDatasource in the code behind and binding to the datasource property
When I use the declarative method (1), sorting works fine without any extra work on my part, but If I create the SqlDatasource in the code behind and try to sort, I get an exception saying 'The GridView 'myGridView' fired event Sorting which wasn't handled'.
I assume that there is some sort of extra plumbing that occurs when using the first method. Does anyone know what the datasourceid method does that the programmatic one doesn't? I would like to duplicate the logic in the code behind if possible.
