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  • class __init__ (not instance __init__)

    - by wallacoloo
    Here's a very simple example of what I'm trying to get around: class Test(object): some_dict = {Test: True} The problem is that I cannot refer to Test while it's still being defined Normally, I'd just do this: class Test(object): def __init__(self): self.__class__.some_dict = {Test: True} But I never create an instance of this class. It's really just a container to hold a group of related functions and data (I have several of these classes, and I pass around references to them, so it is necessary for Test to be it's own class) So my question is, how could I refer to Test while it's being defined, or is there something similar to __init__ that get's called as soon as the class is defined? If possible, I want self.some_dict = {Test: True} to remain inside the class definition. This is the only way I know how to do this so far: class Test(object): @classmethod def class_init(cls): cls.some_dict = {Test: True} Test.class_init()

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  • Derive abstract class from non-abstract class

    - by Jehof
    Is it OK to derive an abstract class from a non-abstract class or is there something wrong with this approach? Here´s a little example: public class Task { // Some Members } public abstract class PeriodicalTask : Task { // Represents a base class for task that has to be done periodicaly. // Some additional Members } public class DailyTask : PeriodicalTask { // Represents a Task that has to be done daily. // Some additional Members } public class WeeklyTask : PeriodicalTask { // Represents a Task that has to be done weekly. // Some additional Members } In the example above i do not want to make the class Task abstract, because i want to instantiate it directly. PeriodicalTask should inherit the functionality from Task and add some additional members but i do not want to instantiate it directly. Only derived class of PeriodicalTask should be instantiated.

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  • Java - abstract class, equals(), and two subclasses

    - by msr
    Hello, I have an abstract class named Xpto and two subclasses that extend it named Person and Car. I have also a class named Test with main() and a method foo() that verifies if two persons or cars (or any object of a class that extends Xpto) are equals. Thus, I redefined equals() in both Person and Car classes. Two persons are equal when they have the same name and two cars are equal when they have the same registration. However, when I call foo() in the Test class I always get "false". I understand why: the equals() is not redefined in Xpto abstract class. So... how can I compare two persons or cars (or any object of a class that extends Xpto) in that foo() method? In summary, this is the code I have: public abstract class Xpto { } public class Person extends Xpto{ protected String name; public Person(String name){ this.name = name; } public boolean equals(Person p){ System.out.println("Person equals()?"); return this.name.compareTo(p.name) == 0 ? true : false; } } public class Car extends Xpto{ protected String registration; public Car(String registration){ this.registration = registration; } public boolean equals(Car car){ System.out.println("Car equals()?"); return this.registration.compareTo(car.registration) == 0 ? true : false; } } public class Teste { public static void foo(Xpto xpto1, Xpto xpto2){ if(xpto1.equals(xpto2)) System.out.println("xpto1.equals(xpto2) -> true"); else System.out.println("xpto1.equals(xpto2) -> false"); } public static void main(String argv[]){ Car c1 = new Car("ABC"); Car c2 = new Car("DEF"); Person p1 = new Person("Manel"); Person p2 = new Person("Manel"); foo(p1,p2); } }

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  • LaTeX book class: Twosided document with wrong margins

    - by fgysin
    I am trying to write my thesis in latex... Cannot get the layout straight though :? I'm using the following document class: \documentclass[11pt,a4paper,twoside,openright]{book} My problem is: on the odd numbered pages there is a big margin right, and a small margin left - it should be the other way round... (for binding & stuff) I am a little puzzled by this - am I just to stupid to see the obvious? The odd page numbers appear on the 'right' page of a bound document, so there needs to be a larger margin left for bindin. Right? Why does LaTeX not behave like this? Here is the full code to produce a small Tex file that shows my problem: \documentclass[11pt,a4paper,twoside,openright]{book} \begin{document} \chapter{blah} Lorem ipsum ius et accumsan tractatos, aliquip deterruisset cu usu. Ea soleat eirmod nostrud eum, est ceteros similique ad, at mea tempor petentium. At decore neglegentur quo, ea ius doming dictas facilis, duo ut porro nostrum suavitate. \end{document}

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  • VIrtual class problem

    - by ugur
    What i think about virtual class is, if a derived class has a public base, let's say, class base, then a pointer to derived can be assigned to a variable of type pointer to base without use of any explicit type conversion. But what if, we are inside of base class then how can we call derived class's functions. I will give an example: class Graph{ public: Graph(string); virtual bool addEdge(string,string); } class Direct:public Graph{ public: Direct(string); bool addEdge(string,string); } Direct::Direct(string filename):Graph(filename){}; When i call constructor of Direct class then it calls Graph. Now lets think Graph function calls addedge. Graph(string str){ addedge(str,str); } When it calls addedge, even if the function is virtual, it calls Graph::edge. What i want is, to call Direct::addedge. How can it be done?

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  • Virtual class problem

    - by ugur
    What i think about virtual class is, if a derived class has a public base, let's say, class base, then a pointer to derived can be assigned to a variable of type pointer to base without use of any explicit type conversion. But what if, we are inside of base class then how can we call derived class's functions. I will give an example: class Graph{ public: Graph(string); virtual bool addEdge(string,string); } class Direct:public Graph{ public: Direct(string); bool addEdge(string,string); } Direct::Direct(string filename):Graph(filename){}; When i call constructor of Direct class then it calls Graph. Now lets think Graph function calls addedge. Graph(string str){ addedge(str,str); } When it calls addedge, even if the function is virtual, it calls Graph::edge. What i want is, to call Direct::addedge. How can it be done?

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  • inserting selected page from one word document in another word document with c#

    - by daemonkid
    I have a requirement to move selected pages from word DocumentA into another word DocumentB. So in the end DocumentB should have its own contents plus selected pages from DocumentA inserted at selected pages in DocumentB. The page number in DocumentB I will set thru properties. This is the code I am using to just append contents of DocumentA to DocumentB. object missing = System.Reflection.Missing.Value; Word._Application wordApp = new Word.Application(); Word._Document aDoc = new Word.Document(); try { wordApp.Visible = false; object readOnly = false; object isVisible = false; aDoc = wordApp.Documents.Open(ref fPath1, ref missing, ref readOnly, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref isVisible, ref missing, ref missing, ref missing, ref missing); Word.Selection selection = wordApp.Selection; selection.InsertFile(fPath2, ref missing, ref missing, ref missing, ref missing); aDoc.Save(); wordApp.Quit(ref missing, ref missing, ref missing); } catch(Exception ex) { throw new Exception(ex.Message); } finally { wordApp = null; aDoc = null; } However, I keep getting this exception 'object reference not set to instance of object' at the line 'selection.InsertFile...' What is going wrong here? And how do I insert contents of page 2 from DocumentA into page 3 of DocumentB? Thanks for your time.

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  • Flash AS3 - Dispatching Events from Parent Class to Child Class

    - by John Russell
    I think this is a pretty simply problem but I do not seem to be able to pull it off. Basically I have a parent class A, and a child class B. Class A instantiates class B with addChild. There is a shared object which is being updated from a java server (red5) that has an event listener attached to it in class A. I have a function in class A which will pass certain, specific updates from this shared object to class B. The problem occurs is that when class B is instantiated, the event listener from class A doesn't work anymore. I have not removed the event listener from A. Any thoughts?

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  • Python overriding class (not instance) special methods

    - by André
    How do I override a class special method? I want to be able to call the __str__() method of the class without creating an instance. Example: class Foo: def __str__(self): return 'Bar' class StaticFoo: @staticmethod def __str__(): return 'StaticBar' class ClassFoo: @classmethod def __str__(cls): return 'ClassBar' if __name__ == '__main__': print(Foo) print(Foo()) print(StaticFoo) print(StaticFoo()) print(ClassFoo) print(ClassFoo()) produces: <class '__main__.Foo'> Bar <class '__main__.StaticFoo'> StaticBar <class '__main__.ClassFoo'> ClassBar should be: Bar Bar StaticBar StaticBar ClassBar ClassBar Even if I use the @staticmethod or @classmethod the __str__ is still using the built in python definition for __str__. It's only working when it's Foo().__str__() instead of Foo.__str__().

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  • Problem with document.location.href

    - by novellino
    Hello, I am new to Javascript and Web development and I have a question regarding the document.location.href. I am using a cookie for storing the language the user prefers and then load the english or the swedish version depending on the language. The default language in the beginning is the same as the browser's language, and my index.jsp is the swedish one. The first time everything works fine. The problem is when the cookie exists already. The basic code is: if (language!=null && language!=""){ if (language=="en-US" || language=="en-us") document.location.href = "en/index.jsp"; } else{ //Explorer if (navigator.userLanguage) language = navigator.userLanguage; //other browsers else language = (navigator.language) ? navigator.language : navigator.userLanguage; if (language!=null && language!=""){ setCookie('language', language, 365, '/', 'onCheck'); if (language=="en-US" || language=="en-us") document.location.href = "en/index.jsp"; else if(language=="sv") document.location.href="index.jsp"; } } When the cookie exists we enter the first "if", and there, if the language is swedish it opens the default blabla/index.jsp page. When the language is set to engish it should open the blabla/en/index.jsp but instead it opens the blabla/en/en/index.jsp which of course is wrong. Does anyone know what I am doing wrong?? Thanks

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  • Override bits of a CSS class while inline?

    - by larryq
    I have an html img that is being styled by a CSS class. I would like to override the width and height values used in that class under some circumstances. I'm building this img tag using something called a TagBuilder class, provided by Microsoft for the .Net system, which allows developers to assign attributes to an html element. In this case a CSS class has been assigned to the img tag, and I can assign width and height attributes individually, but they're not taking precedence over the values set in the CSS class. My tag looks like this currently: <img alt="my link" class="static" height="240" id="StaticImage" src="http://imageserver.com/myImage.jpg" width="240"> The static CSS class has width and height values of 300 each, and as you can see I'm trying to override them with 240. It's not working in this instance but can I do it without a second CSS class?

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  • python class attribute

    - by chnet
    Hi, i have a question about class attribute in python. class base : def __init__ (self): pass derived_val = 1 t1 = base() t2 = base () t2.derived_val +=1 t2.__class__.derived_val +=2 print t2.derived_val # its value is 2 print t2.__class__.derived_val # its value is 3 The results are different. I also use id() function to find t2.derived_val and t2.class.derived_val have different memory address. My problem is derived_val is class attribute. Why it is different in above example? Is it because the instance of class copy its own derived_val beside the class attribute?

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  • Javascript document.open asynchronous?

    - by Alex Schneider
    So on my site there is a Javascript function that will load a new site from the server via XMLHttpRequest. After that it replaces the current page with the new one: var post = new XMLHttpRequest(); post.open('POST', data); post.onload = function() { var do = document.open("text/html", "replace"); do.write(post.responseText); do.close(); goOn(); } function goOn() { console.log($('img:visible')); } Some could assume that after do.close() the document has changed and is ready. But it is not, e.g. if i load very much/big data/responseText the function goOn() only logs an empty result. Obviously goOn() gets in that case called before the DOM is ready to be read! Unfortunately the is no "ready" event fired after write() finished.... How can i be sure it is finished? /EDIT: goOn() logs this to Chrome Console: [prevObject: p.fn.p.init[1], context: #document, selector: "img:visible"] context: #document length: 0 prevObject: p.fn.p.init[1] selector: "img:visible" __proto__: Object[0] But if i right after that type $('img:visible') into console manually it shows me all images....

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  • Python Class inherit from all submodules

    - by Dhruv Govil
    I'm currently writing a wrapper in python for a lot of custom company tools. I'm basically going to break each tool into its own py file with a class containing the call to the tool as a method. These will all be contained in a package. Then there'll be a master class that will import all from the package, then inherit from each and every class, so as to appear as one cohesive class. masterClass.py pyPackage - __ init__.py - module1.py --class Module1 ---method tool1 - module2.py --class Module2 ---method tool2 etc Right now, I'm autogenerating the master class file to inherit from the packages modules, but I was wondering if there was a more elegant way to do it? ie from package import * class MasterClass(package.all): pass

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  • Beginner Geek: Scan a Document or Picture in Windows 7

    - by Mysticgeek
    There may come a time when you want to digitize your priceless old pictures, or need to scan a receipts and documents for your company. Today we look at how to scan a picture or document in Windows 7. Scanning Your Document In this example we’re using an HP PSC 1500 All-In-One printer connected to a Windows 7 Home Premium 32-bit system. Different scanners will vary, however the process is essentially the same. The scanning process has changed a bit since the XP days. To scan a document in Windows 7, place the document or picture in the scanner, click on Start, and go to Devices and Printers.   When the Devices and Printers window opens, find your scanning device and double-click on it to get the manufacturers Printer Actions menu. For our HP PSC 1500 we have a few different options like printing, device setup, and scanner actions. Here we’ll click on the Scan a document or photo hyperlink. The New Scan window opens and from here you can adjust the quality of the scanned image and choose the output file type. Then click the Preview button to get an idea of what the image will look like.   If you’re not happy with the preview, then you can go back and make any adjustments to the quality of the document or photo. Once everything looks good, click on the Scan button. The scanning process will start. The amount of time it takes will depend on your scanner type, and the quality of the settings you choose. The higher the quality…the more time it will take. You will have the option to tag the picture if you want to… Now you can view your scanned document or photo inside Windows Photo Viewer. If you’re happy with the look of the document, you can send it off in an email, put it on an network drive, FTP it… whatever you need to do with it. Another method is to place the document of photo you wish to scan in the scanner, open up Devices and Printers, then right-click on the scanning device and select Start Scan from the context menu. This should bypass the manufacturer screen and go directly into the New Scan window, where you can start the scan process. From the Context Menu you can also choose Scan Properties. This will allow you to test the scanner if you’re having problems with it and change some of its settings. Or you can choose Scan Profiles which allows you to use pre-selected settings, create your own, or set one as the default. Although scanning documents and photos isn’t a common occurrence as it was a few years ago, Windows 7 still includes the feature. When you need to scan a document or photo in Windows 7, this should get you started. Similar Articles Productive Geek Tips Easily Rotate Pictures In Word 2007Beginner Geek: Delete User Accounts in Windows 7Customize Your Welcome Picture Choices in Windows VistaSecure Computing: Detect and Eliminate Malware Using Windows DefenderMark Your Document As Final in Word 2007 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips VMware Workstation 7 Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Creating a Password Reset Disk in Windows Bypass Waiting Time On Customer Service Calls With Lucyphone MELTUP – "The Beginning Of US Currency Crisis And Hyperinflation" Enable or Disable the Task Manager Using TaskMgrED Explorer++ is a Worthy Windows Explorer Alternative Error Goblin Explains Windows Error Codes

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  • jQuery(document).ready doesn't run under IIS7

    - by gsiler
    To simplify this test case, I created a new default .NET MVC project in Visual Studio 2010, and added the following code to the HTML header in Site.Master: <script type="text/javascript" src="../../Scripts/jquery-1.4.1.js"></script> <script type="text/javascript"> jQuery(document).ready(function () { alert('jQuery document ready'); }); </script> This works as expected in the .NET development server. However, when deployed to IIS7, the jQuery(document).ready function is not executed. Needless to say, my actual application is much more complicated. This eliminates all "suspects" except IIS7 deployment. Any thoughts/suggestions?

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  • Newly created Document library are not visible on sharepoint using webservices

    - by Royson
    Hi, I am able to create Document library. Lists listService = new Lists(); listService.PreAuthenticate = true; listService.Credentials = new NetworkCredential(username,password,domain; String url = "http://YourServer/SiteName/"; listService.Url = url @ + /_vti_bin/lists.asmx"; XmlNode ndList = listService.AddList(NewListName, "Description", 101); It is working successfully. But Problem i am facing is: New Document library are not visible in site. I tried with comparing Field Value of Both Visible and No-Visible Document library. Difference i found is : Visible Library (Created Manually) doesn't contain Version value. were as it it present in library which are created by this code. Can you help me out in this?

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  • cast operator to base class within a thin wrapper derived class

    - by miked
    I have a derived class that's a very thin wrapper around a base class. Basically, I have a class that has two ways that it can be compared depending on how you interpret it so I created a new class that derives from the base class and only has new constructors (that just delegate to the base class) and a new operator==. What I'd like to do is overload the operator Base&() in the Derived class so in cases where I need to interpret it as the Base. For example: class Base { Base(stuff); Base(const Base& that); bool operator==(Base& rhs); //typical equality test }; class Derived : public Base { Derived(stuff) : Base(stuff) {}; Derived(const Base& that) : Base(that) {}; Derived(const Derived& that) : Base(that) {}; bool operator==(Derived& rhs); //special case equality test operator Base&() { return (Base&)*this; //Is this OK? It seems wrong to me. } }; If you want a simple example of what I'm trying to do, pretend I had a String class and String==String is the typical character by character comparison. But I created a new class CaseInsensitiveString that did a case insensitive compare on CaseInsensitiveString==CaseInsensitiveString but in all other cases just behaved like a String. it doesn't even have any new data members, just an overloaded operator==. (Please, don't tell me to use std::string, this is just an example!) Am I going about this right? Something seems fishy, but I can't put my finger on it.

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  • Getting the name of a child class in the parent class (static context)

    - by Benoit Myard
    Hi everybody, I'm building an ORM library with reuse and simplicity in mind; everything goes fine except that I got stuck by a stupid inheritance limitation. Please consider the code below: class BaseModel { /* * Return an instance of a Model from the database. */ static public function get (/* varargs */) { // 1. Notice we want an instance of User $class = get_class(parent); // value: bool(false) $class = get_class(self); // value: bool(false) $class = get_class(); // value: string(9) "BaseModel" $class = __CLASS__; // value: string(9) "BaseModel" // 2. Query the database with id $row = get_row_from_db_as_array(func_get_args()); // 3. Return the filled instance $obj = new $class(); $obj->data = $row; return $obj; } } class User extends BaseModel { protected $table = 'users'; protected $fields = array('id', 'name'); protected $primary_keys = array('id'); } class Section extends BaseModel { // [...] } $my_user = User::get(3); $my_user->name = 'Jean'; $other_user = User::get(24); $other_user->name = 'Paul'; $my_user->save(); $other_user->save(); $my_section = Section::get('apropos'); $my_section->delete(); Obviously, this is not the behavior I was expecting (although the actual behavior also makes sense).. So my question is if you guys know of a mean to get, in the parent class, the name of child class.

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  • Document Based Application, preinitialize window (enter serial, buy, trial)

    - by Remizorrr
    I need to create several windows before NSDocument is loaded, or create a window that blocks NSDocument window and top menu. I tried several solutions - but they didn't work right. modal window, one after another. there were some problems with Async URLConnection, and some other problems with my NSDocument content. I created custom MainMenu.xib with no menu, that opens my preinitialize windows. here i found some other problems, when a file(associated with my application) is opened - the Document Window initializes. Here i tried to subclass NSDocumentController, but i found no way to pause the "open document". (i want the document to be opened anyway, but only after the preinitalize windows would be closed). So what is the right way to do this?

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  • Portable and Secure Document Repository

    - by Sivakanesh
    I'm trying to find a document manager/repository (WinXP) that can be used from a USB disk. I would like a tool that will allow you to add all documents into a single repository (or a secure file system). Ideally you would login to this portable application to add or retrieve a document and document shouldn't be accessible outside of the application. I have found an application called Benubird Pro (app is portable) that allows you to add files to a single repository, but downsides are that it is not secure and the repository is always stored on the PC and not on the USB disk. Are you able to recommend any other applications? Thanks

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  • Class initialization and synchronized class method

    - by nybon
    Hi there, In my application, there is a class like below: public class Client { public synchronized static print() { System.out.println("hello"); } static { doSomething(); // which will take some time to complete } } This class will be used in a multi thread environment, many threads may call the Client.print() method simultaneously. I wonder if there is any chance that thread-1 triggers the class initialization, and before the class initialization complete, thread-2 enters into print method and print out the "hello" string? I see this behavior in a production system (64 bit JVM + Windows 2008R2), however, I cannot reproduce this behavior with a simple program in any environments. In Java language spec, section 12.4.1 (http://java.sun.com/docs/books/jls/second_edition/html/execution.doc.html), it says: A class or interface type T will be initialized immediately before the first occurrence of any one of the following: T is a class and an instance of T is created. T is a class and a static method declared by T is invoked. A static field declared by T is assigned. A static field declared by T is used and the reference to the field is not a compile-time constant (§15.28). References to compile-time constants must be resolved at compile time to a copy of the compile-time constant value, so uses of such a field never cause initialization. According to this paragraph, the class initialization will take place before the invocation of the static method, however, it is not clear if the class initialization need to be completed before the invocation of the static method. JVM should mandate the completion of class initialization before entering its static method according to my intuition, and some of my experiment supports my guess. However, I did see the opposite behavior in another environment. Can someone shed me some light on this? Any help is appreciated, thanks.

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  • How do you do real time document tracking?

    - by Nimish
    I was considering diff Document Tracking options and came across DocTracking.com. DocTracking.com allows you to upload documents (PDF Word etc) and adds some kind of invisible tracking to it and returns the document to you which can then be used just like you would use the document otherwise. This tracking tells you when your documents were opened, who opened them (IP), geo-location of opening if they are re-opened or forwarded, what pages were read and how long it was read for, what was printed. Any leads on how this could be done would be appreciated.

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  • Breaking through the class sealing

    - by Jason Crease
    Do you understand 'sealing' in C#?  Somewhat?  Anyway, here's the lowdown. I've done this article from a C# perspective, but I've occasionally referenced .NET when appropriate. What is sealing a class? By sealing a class in C#, you ensure that you ensure that no class can be derived from that class.  You do this by simply adding the word 'sealed' to a class definition: public sealed class Dog {} Now writing something like " public sealed class Hamster: Dog {} " you'll get a compile error like this: 'Hamster: cannot derive from sealed type 'Dog' If you look in an IL disassembler, you'll see a definition like this: .class public auto ansi sealed beforefieldinit Dog extends [mscorlib]System.Object Note the addition of the word 'sealed'. What about sealing methods? You can also seal overriding methods.  By adding the word 'sealed', you ensure that the method cannot be overridden in a derived class.  Consider the following code: public class Dog : Mammal { public sealed override void Go() { } } public class Mammal { public virtual void Go() { } } In this code, the method 'Go' in Dog is sealed.  It cannot be overridden in a subclass.  Writing this would cause a compile error: public class Dachshund : Dog { public override void Go() { } } However, we can 'new' a method with the same name.  This is essentially a new method; distinct from the 'Go' in the subclass: public class Terrier : Dog { public new void Go() { } } Sealing properties? You can also seal seal properties.  You add 'sealed' to the property definition, like so: public sealed override string Name {     get { return m_Name; }     set { m_Name = value; } } In C#, you can only seal a property, not the underlying setters/getters.  This is because C# offers no override syntax for setters or getters.  However, in underlying IL you seal the setter and getter methods individually - a property is just metadata. Why bother sealing? There are a few traditional reasons to seal: Invariance. Other people may want to derive from your class, even though your implementation may make successful derivation near-impossible.  There may be twisted, hacky logic that could never be second-guessed by another developer.  By sealing your class, you're protecting them from wasting their time.  The CLR team has sealed most of the framework classes, and I assume they did this for this reason. Security.  By deriving from your type, an attacker may gain access to functionality that enables him to hack your system.  I consider this a very weak security precaution. Speed.  If a class is sealed, then .NET doesn't need to consult the virtual-function-call table to find the actual type, since it knows that no derived type can exist.  Therefore, it could emit a 'call' instead of 'callvirt' or at least optimise the machine code, thus producing a performance benefit.  But I've done trials, and have been unable to demonstrate this If you have an example, please share! All in all, I'm not convinced that sealing is interesting or important.  Anyway, moving-on... What is automatically sealed? Value types and structs.  If they were not always sealed, all sorts of things would go wrong.  For instance, structs are laid-out inline within a class.  But what if you assigned a substruct to a struct field of that class?  There may be too many fields to fit. Static classes.  Static classes exist in C# but not .NET.  The C# compiler compiles a static class into an 'abstract sealed' class.  So static classes are already sealed in C#. Enumerations.  The CLR does not track the types of enumerations - it treats them as simple value types.  Hence, polymorphism would not work. What cannot be sealed? Interfaces.  Interfaces exist to be implemented, so sealing to prevent implementation is dumb.  But what if you could prevent interfaces from being extended (i.e. ban declarations like "public interface IMyInterface : ISealedInterface")?  There is no good reason to seal an interface like this.  Sealing finalizes behaviour, but interfaces have no intrinsic behaviour to finalize Abstract classes.  In IL you can create an abstract sealed class.  But C# syntax for this already exists - declaring a class as a 'static', so it forces you to declare it as such. Non-override methods.  If a method isn't declared as override it cannot be overridden, so sealing would make no difference.  Note this is stated from a C# perspective - the words are opposite in IL.  In IL, you have four choices in total: no declaration (which actually seals the method), 'virtual' (called 'override' in C#), 'sealed virtual' ('sealed override' in C#) and 'newslot virtual' ('new virtual' or 'virtual' in C#, depending on whether the method already exists in a base class). Methods that implement interface methods.  Methods that implement an interface method must be virtual, so cannot be sealed. Fields.  A field cannot be overridden, only hidden (using the 'new' keyword in C#), so sealing would make no sense.

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