Never seen this before in ASP.NET development.
I'm trying to refactor out 40 single-page ASP.NET pages to code-behind style.
What does this code do?
// Validate required parameters (if "new", then nothing is required)
if (!this.IsNew())
{
if (string.IsNullOrEmpty(_billId))
{
responseErrorNo = 4;
Utils.SendError(respErrNum);
}
}
Its on a single-page design ASP.NET page in the block in the Page_Load method.
On a code-behind page this code ( .IsNew) is not recognized. What am I missing here?
Is there an MSDN page on IsNew of the "page"?
update
Ok. This is my dumbkoff move of the day.
There was a little method hidding at the bottom of the server-side
was protected bool IsNew()
see comments about the inheritance point.
http://msdn.microsoft.com/en-us/library/015103yb.aspx
Have you done a search through all the source files for IsNew?
Some possibilities
1. This is a method inherited from a base class, if you have one of course
2. IsNew might be an extension method. http://msdn.microsoft.com/en-us/library/bb383977.aspx
3. IsNew is a member of the class
If your code-behind file inherits from a custom page class, as in a class like PageBase instead of the standard System.Web.UI.page, the IsNew could be in there, and maybe your page needs to implement that... ALtneratively, it could be an extension method for the page class, and your missing the namespace reference to include it...
HTH.
This is puzzling as the System.Web.UI.Page class definitely has no IsNew() method. The only way you would get that is if the page is inheriting from a base page, or perhaps if it there is an extension method that extends Page.
Can you right-click the method in Visual Studio and find the definition?
Related
There is an abstract base page
public abstract class BasePage : PageData
There are some pages that are inherited from this page
public class ChildPage : BasePage
public class ChildPage2 : BasePage
I need to retrieve all the pages that are inherited from the BasePage.
In PropertyCriteria I could use only ChildPage and ChildPage2 for the search by PageTypeID. So this approach would not solve the issue in my case
Your most viable options are to 1) retrieve all pages (with GetChildren or GetDescendants, depending on content structure) of the base type, or 2) use Find.
Episerver Find makes this kind of thing trivial, provided your site actually uses Find. :/
A third (not recommended) option would be to identify all of the sub-types and use multiple FindPagesWithCriteria calls, but that would be slow. FPWC is entirely uncached, and results in DB calls.
Personally, I never use FindPagesWithCriteria for anything other than certain administrative features not dealing with rendering the actual site.
I have a method in an aspx web page which is accessed from another non webpage .cs class. This method contains a ClientScript to create a popup.
I get this error below when trying to make it a static.
An object reference is required for the non-static field, method, or property 'System.Web.UI.Page.ClientScript.get'
So I am wondering if there is a way to access this method from another .cs class or a solution.
Basically when an error trips on the .cs class I want to display a popup that says the error.
public static void message(string popupinformation)
{
ClientScript.RegisterStartupScript(this.GetType(), "", "popupinformation", true);
}
In .cs
AddUI.message("alert('Error can not add information');");
tl;dr - You need to add "System.web" reference in that library.
I understand that, you have a separated cs file in some another library that invokes a function sitting in asp.net webform. If that is true, then how you are calling that function because it will be inside a page class which inherits from system.web.ui.page.
Lets assume you have make it work by placing that in App_Code. Then used that class say Web_work.cs in some other library say lib.cs.
To use ClientScript... in the library with lib.cs you need to add "System.web" reference in that library.
Best practice is to do all validation in library, but use such kind of display method in webform only. Take an example, lets say you want to use windows form now, which uses MessageBox.Show, in that case your library needs change with current approach.
I have a method in a class like below:
public class ActionHelper
{
[DirectMethod]
public string DeleteComment()
{
...
return "Delete";
}
}
and I want to call it from grid command like this:
<Command Handler="Ext.net.DirectMethod.request({url: '/Classes/ActionHelper/DeleteComment', cleanRequest: true}});" />
but it's not working! how can i do that??? I use ext.net 2.2 and .netframework 4.5
look at this example
http://examples.ext.net/#/Events/DirectMethods/ID_Mode/
it can be helpful
Put a [DirectMethod] in your code behind wich calls that class and use
App.direct.<Method>(); instead
You can't, you either define the method inside the Page, User Control or any Custom Control, or you define a static method inside the Page class.
Here is a quote defining direct methods from a post in the Ext.net forums:
DirectMethod (none static, must be public): server side handler is
raised when you call special javascript method (basically, proxy
method is generated by Ext.Net toolkit). None static direct method can
be defined inside Page, User Control or any Custom Control. Please
note, if direct method is defined inside user control (master page
placeholders are user controls also) or custom control then ClientID
of that control will be added to proxy method 1
Ext.net.DirectMethods.ClientIDOfTheControl.DirectMethodName(); You can
use DirectMethodProxyID attribute for the class to define own alias or
completely remove ClientID prefix Really, none static direct method is
direct event. Single difference, that direct method has no relation
with any widget (and its events) and can be raised by developer from
javascript (as javascript method)
Static DirectMethod (must be public): similar ASP.NET PageMethods, can be defined inside Page class only. With static page method the
Page life cyle is not execued therefore access to ASP.NET control is
not possible but response time much better (depends from your method
logic only)
I've read the questions/answers explaining that there is no multiple inheritance in C#, that we don't even need it, and that it causes too much problems.
Now, I'm working on a project where I don't really understand how can I do things without multiple inheritance, without duplicating code.
Here's the situation. There is a website with a home page and other pages inheriting from a masterpage (the home page does not inherit from). Both the page and the masterpage are performing some stuff: custom login, statistics, loading of users settings for customization, etc. For the moment, the solution is crappy, since the source code for those tasks is just copied twice.
The home page class inherits from Page. The masterpage, on the other hand, inherits from Masterpage. Logically, it would be great to inherit from a common class too, but it's multiple inheritance, so it's impossible.
So what to do instead?
I thought about several ways, but dislike them:
Create a standalone class which will be called from the page/masterpage class. So for example instead of writing bool isDisplayingTips = this.CurrentUser.IsDisplayingTips, I would write bool isDisplayingTips = this.SharedObjects.CurrentUser.IsDisplayingTips. I don't like it, since it's longer to write.
Create a "real", empty, common masterpage, and inherit both the home page and the masterpage from it. Not only it will require to write more code to access masterpage parameters, but it will also slow the things down, requiring an additional masterpage on each request.
Any idea?
MasterPage is a just control (that get embedded into the actual page) so you can not have the later approach. However, first approach of creating another helper class is quite feasible.
Yet another approach that we typically use is to have
Common base page class - all pages will inherit from the common base page.
Put common functionality in base page class
From master page, the base page can be referred by casting - for example, myBasePage = (BasePage)this.Page;. This way master page may access common functionality from base page class.
I don't find your 2nd option that dislikable.
I presume you mean creating a base class, e.g. MasterPageBase, derived from System.Web.UI.MasterPage, and creating an empty MasterPage for your homepage, that will inherit from this MasterPageBase.
If done right, it shouldn't slow things down...
I suggest you to use the first of your option. If you (understandably)
don't feel comfortable with increased level of indirection, you could just create new methods on your standalone classe, e.g:
public bool IsDisplayingTips(){
return CurrentUser.IsDisplayingTips;
}
and the from your pages just call
bool isDisplayingTips = this.SharedObjects.IsDisplayingTips()
Use:
standalone class which will be called
from the page/masterpage class
but instead of stopping there, add a base page and a base master page. Both use the shared class, and keep the specific pages/master pages code from the indirection.
I have a set of functions I want to be available to my web pages and user controls in my c# .net 3.5 web project. My standard approach for pages is to create a "base page" that extends the System.Web.UI.Page class and then have my pages inherit from this, rather than directly from the Page class.
I now want to expose some of these functions to my web controls (ascx) and web services. I can think of a number of ways to do this, but they seem a little clumsy and I think I'm missing a trick.
Is there an easy way to provide some common functions to both my pages, web services and controls using inheritance, or do I need to wrap these functions in a class that all of them can access?
An example to clarify:
I have a singleton that handles most functionality for my web application.
At the start of each request I want to check that the class exists in the web cache and initialise it if not.
Initially this was handled in a page base that the pages all used. Now I need to be able to access my singleton safely from services and controls, with the same checks. I have therefore extracted the checking and initialisation logic into another class, that then each of my base page, control and web service, all instantiate. Even with this model I have the same code repeated in 3 places (each of my base classes for controls, ws and pages), albeit not much code, this seems wrong too!
It works, but it seems clumsy...I look forward to you guys humbling me with your wisdom!
Sounds to mee like a case of aspect-oriented programming. .NET is ill equipped for this. I'm afraid that your solution is one of the best.
Alternatively perhaps you can move all or some of those functions to a static class/singleton and then use that class from your aspx/ascx/asmx? Not much in the way of inheritance, but at least less code duplication.
My solution to this is to put all the methods and functions I want to share in my base master page class. I then put an equivalent for each method and function in the user control base class as follows:
//Property in masterpage base
public string QsSearchTerm
{
get
{
if (!String.IsNullOrEmpty(Request.QueryString["q"]))
{
return Helpers.SanitiseString(Server.UrlDecode(Request.QueryString["q"]));
}
return String.Empty;
}
}
//Property in usercontrol base
public string QsSearchTerm
{
get
{
if (Page.Master is BaseMasterPage)
{
return ((BaseMasterPage)Page.Master).QsSearchTerm;
}
return string.Empty;
}
}
What this doesn't help with, is your code repetition with web service base classes. I would think that refactoring the above into a class with a constructor that accepts an HttpContext instance would be the way forward. You can then expose a singleton instance of this class in your base web service, master page, user control, page etc.
Hope this helps, but I too would be interested in hearing if there's a better way.
In your Singleton you could provide a Strategy interface to allow variations of the code depending on the configured environment. This would allow you to switch between web/windows/wcf...and so on.
I think using a BasePage is the right approach.
I have multiple base pages and custom user controls that load differently depending on which basepage is used by the current page.
In your custom user control you can use something like:
if (this.Page is BasePageName)
{
BasePageName bp = (BasePageName)this.Page;
bp.BasePageFunction();
}
No you can get ride of the repetitive code in the custom user control and just call it from the base page.
You can also have a hierarchy of inherited base pages depending on page functionality and needs. ie.) BasePageName2 : BasePageName