want to make sure I am not assuming something foolish here, when implementing the singleton pattern in an ASP .Net web application the static variable scope is only for the current user session, right? If a second user is accessing the site it is a different memory scope...?
View 4 Replies
In one of the interview, I was asked why should we have to go for Single Design pattern, instead of just creating static methods. Because creating static methods also serve the same purpose, i.;e avoiding flooding of objects.
View 1 RepliesI am looking for differences between those 3 ways of using static class in asp.net application scope.
Will all of these point to the same class?
Which one is preferable >object< defined declaratively inside global.asax or static class ?
examples:
<object runat="server" scope="application" class="classname" ID="objID"></object>
VS
public static class classname {}
VS
Application("a") = new classname();
I want to use Context.Items to store some info of a User Control like:
Context.Items["Data"] = 5;
I want to know, Is Context.Items is for each request or it is global for the application?
I have a class which fetches the data from the database. Say First name, Last name , Telephone number etc and display it in my .aspx page. This data is common to all the users. So i would like to use Singleton pattern so that the object is not created again ,just use the created object for all the users. Can any one help me with the simple code snippet example.
View 3 RepliesI have a web application where I would like to pull user settings from a database and store them for Global access. Would it make more sense to store the data in a Singleton, or a Session object? What's the difference between the two?Is it better to store the data as an object reference or break it up into value type objects (ints and strings)?
View 3 Repliesi'm building a web application with asp.net c# and i have a class that i want to use in multiple pages witouth instantiate it every time. I need to load the data in it and never lose them during the user session time. I thought about the singleton-pattern but it shared the instance of the class beetween browsers.
View 4 RepliesI am working on singleton desing patterns and want some real world example of design patterns.Can you please give me an example how you have used singleton pattern in you project. I would appreciate if you can provide code.
View 3 RepliesI'm developing a blog application shared by non-profit organizations. I want each organization to be able to change their own blog settings. I have taken a singleton pattern (from BlogEngine.net) and modified it. (I understand that it is no longer a singleton pattern.) I have tested this approach and it seems to work fine in a development environment. Is this pattern a good practice? Are there issues, which may arise when this is placed in a production environment?
public class UserBlogSettings
{
private UserBlogSettings()
{
Load();
}
public static UserBlogSettings Instance
{
get
{
string cacheKey = "UserBlogSettings-" + HttpContext.Current.Session["userOrgName"].ToString();
object cacheItem = HttpRuntime.Cache[cacheKey] as UserBlogSettings;
if (cacheItem == null)
{
cacheItem = new UserBlogSettings();
HttpRuntime.Cache.Insert(cacheKey, cacheItem, null, DateTime.Now.AddMinutes(1),
Cache.NoSlidingExpiration);
}
return (UserBlogSettings) cacheItem;
}
}
}
(Portions of code were omitted for brevity.)
I have a whole bunch of data access methods where in each one I am doing this
[Code]....
and them moving on with my SqlCommand and SqlDataReader and so on.Is this creating to many instances of an SQLConnection?I was thinking doing this instead. Creating a SqlConnection Manager which would look like this
[Code]....
and then in my database access methods
[Code]....
Is this a good or bad idea and why?Also would this even be neccesary?
I know what Singleton Pattern means and Abstract class means.What I wanted to know was how would this apply to real world.Could anyone give me any good example or simple explanation.Say I have a simple website, why would I use any of the above if any.Why would it simplify my architechture.
View 3 RepliesIf I were to use singleton pattern for menu, would that cause that menu to be created once for application session or once for each user session. Obviously, I want something that will create menu items once per application session.
View 2 RepliesI understand the problem of the static variable inside a class in the web application, now I try to create a simple class to deal with SQL Server for example, so I created Static Method inside this class, this static method used in insert, update and delete from database, I wonder if this is safe, and there is no problems will appear ?
View 10 RepliesI have searched deference between Static and Singleton Patten on google but did not get it clearly.
View 12 RepliesI have some confusion with singleton class, below are my some points:
1.Can singleton class have static method?,if yes then how we call that methods?
2.what is main difference between Static class and Singleton Class?
I have created my singleton class as follows:
[Code]....
In Above class structure I have created two method one is Static and second is non static, When I am trying to access Static Method it gives me compile time error.
How can I use static method of singleton class?
See in below I have writtine a
1. Singleton class Emp1 with Display Method and
2. Static Class with Static Method Display.
What is the advantage of singleton class over Static Class with Static members?
[Code]....
What is difference between Application object and static variable? Where these are stroed in memory.
View 4 RepliesI need to keep a global variable throughout the whole time the user is at my site, but do I use Application or a static class? The string variable should store a region name and my site makes a few changes depending on which region that has been set.
I read that Application was mainly for classic ASP, but I also read that a static class cannot be instantiated at runtime (e.g. when the user has logged in).
So, have I got something wrong here and which solution do I use?
I have implemented Continuous Page Scrolling according to this post given below [URL] But problem is. How to handle post back events on scrolling e-g On Scrolling i render a user control in ashx handler where I have a asp.net button with click event but don't know how to handle click event because on clicking it does not fire click event except submiting a form and redirect to ashx handler with white screen.
View 1 RepliesI want to declare a variable in such a way that I can access that particular variable and its value in all the asp pages in the project. Can anyone tell me how to declare a variable in C# such that it has project-wide scope?
View 8 RepliesI have a question about C Sharp ASP.NET:Is there a difference (in code speed, resources) between:public static variable declared in public static class MyGlobals in a 'Code File' template;and the variable declared in a normal 'Class File' template;I use this variable in 2 different Class Files and also in _Default Page codebehind cs file.In fact in my case I need about 20 global variables of type List<string>.
View 9 RepliesI have a hierarchy in my website project as below:
[CustomControl1 - folder]
- CustomControl1.ascx
- CustomControl1.css
- CustomControl1.js
I load css and js files dynamicaly based on which controls are used on particular page. I am doing it by using following code:
[code]....
where AddLinks method adds HtmlLink controls to Page.Header with href attribute set to coresponding css and/or js file.
I would like to add Interface that would force new controls to have AddLinks method but it is impossible since it is a static method. Because my custom controls inherit from Control class I cannot use abstract class and/or virtual methods either. How can I achieve my goal?
First of all, I am creating a something like a client/server solution using a standard ASP.NET website - I do know this method is not adviced, and most people would love to scream "COMET!" or "HTML5 Sockets!" - but please don't ;-) !
What I am doing...
I am creating an MMORPG on a website.
I have several clients whom need to be in contact at the same time. This is done by a global object in the Application scope.
My problem
I need to invoke an event to several clients. For instance, when an attack has been performed, I need to update some graphics. The attack logic is resolved in the global object, but each of the clients has to respond to this.
Right now I do the following:
fightTrace.Reciever.InvokeMoveEnded(this);
fightTrace.FiredBy.InvokeMoveEnded(this);
(This is a kind of observer pattern)
What now happends is a race condition. The one who loads the page_load event will get both of these events, and the one who is not running them, will experience no changes in the UI.
So what is it I really want?
What I really need is some genuine and nice way to create an observer pattern through the application state. I need to send an event out to every "listener" which is in this case is a client, and then do some update.
I had an interview today and every thing was going very good, but then an interviewer asked me a question Where Does Static Variable Work in C#- At Application Level or At Page Level.I was not very much clear about this answer as I only knew that static variables are stored on heap and I didn't knew anything about web related thing.
Then he tried to make me more clear by giving an example that in a page I am using static variable and three users are accessing the page one of the user updates the value of static variable, What value will be visible to remaining two users an old copy or the update will be reflected.
I dont know, but <%= %> doesnt allow me to enter my project namespace. Im trying to reference a static variable in another folder.
Ex: <%= Site.Web.Variable %>
