Search Results

Search found 8692 results on 348 pages for 'patterns practices'.

Page 146/348 | < Previous Page | 142 143 144 145 146 147 148 149 150 151 152 153  | Next Page >

  • P/Invoke or C++/CLI for wrapping a C library

    - by Ian G
    Have a moderate size (40-odd function) C API that needs to be called from a C# project. The functions logically break up to form a few classes that will be API presented to the rest of the project. Are there any objective reasons to prefer P/Invoke or C++/CLI for the interoperability underneath that API, in terms of robustness, maintainability, deployment, ...? The issues I could think of that might be, but aren't problematic are: C++/CLI will require an separate assembly, the P/Invoke classes can be in the main assembly. (We've already got multiple assemblies and there'll be the C dlls anyway so not a major issue). Performance doesn't seem differ noticeable between the two methods. Issues that I'm not sure about are: My feeling is C++/CLI will be easier to debug if there's inter-op problem, is this true? Language familiarity enough people know C# and C++ but knowledge of details of C++/CLI are rarer here. Anything else?

    Read the article

  • How to best launch C++ application from web page

    - by JB
    I guess there are two parts to this question, one technical and one best practice for security and doing things "right". I'm working on a little game using C++ / directx but I would like to be able to launch it from a web page by someone clicking on a link on that page. Ideally I would like the first time they clicked for it to launch an installer downloads and installs the game on their machine, and then the next time to launch an application which updates the game from a web site if it's old and then launches it. I have no problems with the expected security popups and questions the first time it runs. I want people to be certain what they are installing and understand what they are doing. But it would be nice if once it is installed they could run it with the minimum of fuss. My question then is what technologies I could use to do this? I'm thinking that it would need a browser plugin and an activex control so that first time you'd install that, and subsequently the control/plugin would be able to launch the game. I'm not sure that under newer browser secuity models that a plugin would have the permissions to be able to run an installer though or silently invoke applications on the client machine even if they are already installed. Is there a more sensible way to achive what I want to achieve? And I'm worried about the security aspects too. I want this to be convenient for users but I of course want to do it "right". I know this can be done as I've seen several mmorpg type games that launch in this way from the browser now but it's not entirely clear to me how they've done it.

    Read the article

  • Which framework exceptions should every programmer know about ?

    - by Thibault Falise
    I've recently started a new project in C#, and, as I was coding some exception throw in a function, I figured out I didn't really know which exception I should use. Here are common exceptions that are often thrown in many programs : ArgumentException ArgumentNullException InvalidOperationException Are there any framework exceptions you often use in your programs ? Which exceptions should every .net programmer know about ? When do you use custom exception ?

    Read the article

  • how can i use switch statement on type-safe enum pattern

    - by Fer
    I found a goodlooking example about implementation enums in a different way. That is called type-safe enum pattern i think. I started using it but i realized that i can not use it in a switch statement. My implementation looks like the following: public sealed class MyState { private readonly string m_Name; private readonly int m_Value; public static readonly MyState PASSED= new MyState(1, "OK"); public static readonly MyState FAILED= new MyState(2, "ERROR"); private MyState(int value, string name) { m_Name = name; m_Value = value; } public override string ToString() { return m_Name; } public int GetIntValue() { return m_Value; } } What can i add to my class in order to be able to use this pattern in switch statements in C#? Thanks.

    Read the article

  • View artifacts leaking into the model of MVC

    - by Jono
    In an ASP.NET MVC application (which has very little chance of having its view technology ported to something non-HTML, but whose functional requirements evolve weekly,) how much HTML should ideally be allowed to be directly represented in the Model? I might come across as a design bigot for this, but I regard it as bad practice to allow any view constructs to "leak" into the model in an MVC application (and vice versa). For example, a Model that represents an item you're about to purchase should know nothing about the HTML check box that says "add giftwrap/message", nor should it know about any HTML drop down lists for payment card types. Conversely the View shouldn't be doing work like figuring out button text by translating keys into values (by looking in resource files.)

    Read the article

  • c++ Design pattern for CoW, inherited classes, and variable shared data?

    - by krunk
    I've designed a copy-on-write base class. The class holds the default set of data needed by all children in a shared data model/CoW model. The derived classes also have data that only pertains to them, but should be CoW between other instances of that derived class. I'm looking for a clean way to implement this. If I had a base class FooInterface with shared data FooDataPrivate and a derived object FooDerived. I could create a FooDerivedDataPrivate. The underlying data structure would not effect the exposed getters/setters API, so it's not about how a user interfaces with the objects. I'm just wondering if this is a typical MO for such cases or if there's a better/cleaner way? What peeks my interest, is I see the potential of inheritance between the the private data classes. E.g. FooDerivedDataPrivate : public FooDataPrivate, but I'm not seeing a way to take advantage of that polymorphism in my derived classes. class FooDataPrivate { public: Ref ref; // atomic reference counting object int a; int b; int c; }; class FooInterface { public: // constructors and such // .... // methods are implemented to be copy on write. void setA(int val); void setB(int val); void setC(int val); // copy constructors, destructors, etc. all CoW friendly private: FooDataPrivate *data; }; class FooDerived : public FooInterface { public: FooDerived() : FooInterface() {} private: // need more shared data for FooDerived // this is the ???, how is this best done cleanly? };

    Read the article

  • Scrum metrics for quality

    - by zachary
    What is the best way to measure QA in scrum? We have members who typically test and they are measured against how many bugs they find. If they don't find any bugs then they are considered to be doing a bad job. However, it is my understanding that the developers and quality people are considered one in the same. I would think that they should be judged against the same metrics... not different metrics then the developers who may also be doing testing work... What is the best way to handle metrics for QA and should QA people have separate metrics from developers in scrum? Any documents or links someone can point me to in regards to this?

    Read the article

  • Is extending a singleton class wrong?

    - by Anwar Shaikh
    I am creating a logger for an application. I am using a third party logger library. In which logger is implemented as singleton. I extended that logger class because I want to add some more static functions. In these static functions I internally use the instance (which is single) of Logger(which i inherited). I neither creates instance of MyLogger nor re-implemented the getInstance() method of super class. But I am still getting warnings like destructor of MyLogger can not be created as parent class (Loggger) destructor is not accessible. I want to know, I am I doing something wrong? Inheriting the singleton is wrong or should be avoided??

    Read the article

  • Including partial views when applying the Mode-View-ViewModel design pattern

    - by Filip Ekberg
    Consider that I have an application that just handles Messages and Users I want my Window to have a common Menu and an area where the current View is displayed. I can only work with either Messages or Users so I cannot work simultaniously with both Views. Therefore I have the following Controls MessageView.xaml UserView.xaml Just to make it a bit easier, both the Message Model and the User Model looks like this: Name Description Now, I have the following three ViewModels: MainWindowViewModel UsersViewModel MessagesViewModel The UsersViewModel and the MessagesViewModel both just fetch an ObserverableCollection<T> of its regarding Model which is bound in the corresponding View like this: <DataGrid ItemSource="{Binding ModelCollection}" /> The MainWindowViewModel hooks up two different Commands that have implemented ICommand that looks something like the following: public class ShowMessagesCommand : ICommand { private ViewModelBase ViewModel { get; set; } public ShowMessagesCommand (ViewModelBase viewModel) { ViewModel = viewModel; } public void Execute(object parameter) { var viewModel = new ProductsViewModel(); ViewModel.PartialViewModel = new MessageView { DataContext = viewModel }; } public bool CanExecute(object parameter) { return true; } public event EventHandler CanExecuteChanged; } And there is another one a like it that will show Users. Now this introduced ViewModelBase which only holds the following: public UIElement PartialViewModel { get { return (UIElement)GetValue(PartialViewModelProperty); } set { SetValue(PartialViewModelProperty, value); } } public static readonly DependencyProperty PartialViewModelProperty = DependencyProperty.Register("PartialViewModel", typeof(UIElement), typeof(ViewModelBase), new UIPropertyMetadata(null)); This dependency property is used in the MainWindow.xaml to display the User Control dynamicly like this: <UserControl Content="{Binding PartialViewModel}" /> There are also two buttons on this Window that fires the Commands: ShowMessagesCommand ShowUsersCommand And when these are fired, the UserControl changes because PartialViewModel is a dependency property. I want to know if this is bad practice? Should I not inject the User Control like this? Is there another "better" alternative that corresponds better with the design pattern? Or is this a nice way of including partial views?

    Read the article

  • [C#][Design] Appropriate programming design questions.

    - by Edward
    I have a few questions on good programming design. I'm going to first describe the project I'm building so you are better equipped to help me out. I am coding a Remote Assistance Tool similar to TeamViewer, Microsoft Remote Desktop, CrossLoop. It will incorporate concepts like UDP networking (using Lidgren networking library), NAT traversal (since many computers are invisible behind routers nowadays), Mirror Drivers (using DFMirage's Mirror Driver (http://www.demoforge.com/dfmirage.htm) for realtime screen grabbing on the remote computer). That being said, this program has a concept of being a client-server architecture, but I made only one program with both the functionality of client and server. That way, when the user runs my program, they can switch between giving assistance and receiving assistance without having to download a separate client or server module. I have a Windows Form that allows the user to choose between giving assistance and receiving assistance. I have another Windows Form for a file explorer module. I have another Windows Form for a chat module. I have another Windows Form form for a registry editor module. I have another Windows Form for the live control module. So I've got a Form for each module, which raises the first question: 1. Should I process module-specific commands inside the code of the respective Windows Form? Meaning, let's say I get a command with some data that enumerates the remote user's files for a specific directory. Obviously, I would have to update this on the File Explorer Windows Form and add the entries to the ListView. Should I be processing this code inside the Windows Form though? Or should I be handling this in another class (although I have to eventually pass the data to the Form to draw, of course). Or is it like a hybrid in which I process most of the data in another class and pass the final result to the Form to draw? So I've got like 5-6 forms, one for each module. The user starts up my program, enters the remote machine's ID (not IP, ID, because we are registering with an intermediary server to enable NAT traversal), their password, and connects. Now let's suppose the connection is successful. Then the user is presented with a form with all the different modules. So he can open up a File Explorer, or he can mess with the Registry Editor, or he can choose to Chat with his buddy. So now the program is sort of idle, just waiting for the user to do something. If the user opens up Live Control, then the program will be spending most of it's time receiving packets from the remote machine and drawing them to the form to provide a 'live' view. 2. Second design question. A spin off question #1. How would I pass module-specific commands to their respective Windows Forms? What I mean is, I have a class like "NetworkHandler.cs" that checks for messages from the remote machine. NetworkHandler.cs is a static class globally accessible. So let's say I get a command that enumerates the remote user's files for a specific directory. How would I "give" that command to the File Explorer Form. I was thinking of making an OnCommandReceivedEvent inside NetworkHandler, and having each form register to that event. When the NetworkHandler received a command, it would raise the event, all forms would check it to see if it was relevant, and the appropriate form would take action. Is this an appropriate/the best solution available? 3. The networking library I'm using, Lidgren, provides two options for checking networking messages. One can either poll ReadMessage() to return null or a message, or one can use an AutoResetEvent OnMessageReceived (I'm guessing this is like an event). Which one is more appropriate?

    Read the article

  • Premature optimization is the root of all evil, but can it ever be too late?

    - by polygenelubricants
    "We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil" So what is that 3% like? Can the avoidance of premature optimization ever be taken too extreme that it does more harm than good? Even if it's rare, has there been a case of a real measurable software engineering disaster due to complete negligence to optimize early in the process? Bonus question: is software engineering pretty much the only field that has such a counter intuitive principle regarding doing something earlier rather than later before things potentially become too big a problem to fix? Personal question: how do you justify something as premature optimization and not just a case of you being lazy/ignorant/dumb?

    Read the article

  • Is there a naming convention for a method that should set the properties of the passed object.

    - by Genady Sergeev
    Hello, I am writing a method that will set the properties of an object passed as a parameter. The method accepts one parameter of type interface and the return type of the method is the same interface. I was wondering if there is some kind of a naming convention for such methods. I was thinking of something like: FillInInterfaceTypeData or InitInterfaceTypeData but both sound clumsy to me. How do you think?

    Read the article

  • Java Code Formating

    - by the qwerty
    I'm using FreeMarker to generate java code, but as most of it is dynamically generated it's difficult to control the code formation. I want to get code well formatted. Does anyone knows a lib or something like a pretty printer for java code?

    Read the article

  • Definitive method for sizing font in css

    - by David
    Hi there, I would like to know some opinions from experienced developers on what they think the definitive way to size fonts (in a base sense). I know that working with ems is considered best but im referring to the best way to set the base font size. There is the technique of setting font to 10px using 62.5 method but i think ie has an issue with rounding which throws this out slightly (perhaps not) YUI framework uses body { font:13px/1.231 arial,helvetica,clean,sans-serif; /* for IE6/7 */ *font-size:small; /* for IE Quirks Mode */ *font:x-small; } which really confuses me! Tripoli uses html { font-size:125%; } body { font-size:50%; } a list apart suggest something along the lines of : body { font-size: 16px; *font-size: 100%; } So which is the best either out of these methods or any alternatives. The best being the easiest to work with and the most reliable cross browser.

    Read the article

  • Python's JSON module doesn't use __get__?

    - by Matt
    When I serialize a list of objects with a custom __get__ method, __get__ is not called and the raw (unprocessed by custom __get__) value from __set__ is used. How does Python's json module iterate over an item? Note: if I iterate over the list before serializing, the correct value returned by __get__ is used.

    Read the article

  • Which design pattern is most appropriate?

    - by Anon
    Hello, I want to create a class that can use one of four algorithms (and the algorithm to use is only known at run-time). I was thinking that the Strategy design pattern sounds appropriate, but my problem is that each algorithm requires slightly different parameters. Would it be a bad design to use strategy, but pass in the relevant parameters into the constructor?. Here is an example (for simplicity, let's say there are only two possible algorithms) ... class Foo { private: // At run-time the correct algorithm is used, e.g. a = new Algorithm1(1); AlgorithmInterface* a; }; class AlgorithmInterface { public: virtual void DoSomething = 0; }; class Algorithm1 : public AlgorithmInterface { public: Algorithm1( int i ) : value(i) {} virtual void DoSomething(){ // Does something with int value }; int value; }; class Algorithm2 : public AlgorithmInterface { public: Algorithm2( bool b ) : value(b) {} virtual void DoSomething(){ // Do something with bool value }; bool value; };

    Read the article

  • Exposing a service to external systems - How should I design the contract?

    - by Larsi
    Hi! I know this question is been asked before here but still I'm not sure what to select. My service will be called from many 3 party system in the enterprise. I'm almost sure the information the service will collect (MyBigClassWithAllInfo) will change during the products lifetime. Is it still a good idea to expose objects? This is basically what my two alternatives: [ServiceContract] public interface ICollectStuffService { [OperationContract] SetDataResponseMsg SetData(SetDataRequestMsg dataRequestMsg); } // Alternative 1: Put all data inside a xml file [DataContract] public class SetDataRequestMsg { [DataMember] public string Body { get; set; } [DataMember] public string OtherPropertiesThatMightBeHandy { get; set; } // ?? } // Alternative 2: Expose the objects [DataContract] public class SetDataRequestMsg { [DataMember] public Header Header { get; set; } [DataMember] public MyBigClassWithAllInfo ExposedObject { get; set; } } public class SetDataResponseMsg { [DataMember] public ServiceError Error { get; set; } } The xml file would look like this: <?xml version="1.0" encoding="utf-8"?> <Message>   <Header>     <InfoAboutTheSender>...</InfoAboutTheSender>   </Header>   <StuffToCollectWithAllTheInfo>   <stuff1>...</stuff1> </StuffToCollectWithAllTheInfo> </Message> Any thought on how this service should be implemented? Thanks Larsi

    Read the article

  • A better UPDATE method in LINQ to SQL

    - by Refracted Paladin
    The below is a typical, for me, Update method in L2S. I am still fairly new to a lot of this(L2S & business app development) but this just FEELs wrong. Like there MUST be a smarter way of doing this. Unfortunately, I am having trouble visualizing it and am hoping someone can provide an example or point me in the right direction. To take a stab in the dark, would I have a Person Object that has all these fields as Properties? Then what, though? Is that redundant since L2S already mapped my Person Table to a Class? Is this just 'how it goes', that you eventually end up passing 30 parameters(or MORE) to an UPDATE statement at some point? For reference, this is a business app using C#, WinForms, .Net 3.5, and L2S over SQL 2005 Standard. Here is a typical Update Call for me. This is in a file(BLLConnect.cs) with other CRUD methods. Connect is the name of the DB that holds tblPerson When a user clicks save() this is what is eventually called with all of these fields having, potentially, been updated-- public static void UpdatePerson(int personID, string userID, string titleID, string firstName, string middleName, string lastName, string suffixID, string ssn, char gender, DateTime? birthDate, DateTime? deathDate, string driversLicenseNumber, string driversLicenseStateID, string primaryRaceID, string secondaryRaceID, bool hispanicOrigin, bool citizenFlag, bool veteranFlag, short ? residencyCountyID, short? responsibilityCountyID, string emailAddress, string maritalStatusID) { using (var context = ConnectDataContext.Create()) { var personToUpdate = (from person in context.tblPersons where person.PersonID == personID select person).Single(); personToUpdate.TitleID = titleID; personToUpdate.FirstName = firstName; personToUpdate.MiddleName = middleName; personToUpdate.LastName = lastName; personToUpdate.SuffixID = suffixID; personToUpdate.SSN = ssn; personToUpdate.Gender = gender; personToUpdate.BirthDate = birthDate; personToUpdate.DeathDate = deathDate; personToUpdate.DriversLicenseNumber = driversLicenseNumber; personToUpdate.DriversLicenseStateID = driversLicenseStateID; personToUpdate.PrimaryRaceID = primaryRaceID; personToUpdate.SecondaryRaceID = secondaryRaceID; personToUpdate.HispanicOriginFlag = hispanicOrigin; personToUpdate.CitizenFlag = citizenFlag; personToUpdate.VeteranFlag = veteranFlag; personToUpdate.ResidencyCountyID = residencyCountyID; personToUpdate.ResponsibilityCountyID = responsibilityCountyID; personToUpdate.EmailAddress = emailAddress; personToUpdate.MaritalStatusID = maritalStatusID; personToUpdate.UpdateUserID = userID; personToUpdate.UpdateDateTime = DateTime.Now; context.SubmitChanges(); } }

    Read the article

  • How to write a good PHP database insert using an associative array

    - by Tom
    In PHP, I want to insert into a database using data contained in a associative array of field/value pairs. Example: $_fields = array('field1'=>'value1','field2'=>'value2','field3'=>'value3'); The resulting SQL insert should look as follows: INSERT INTO table (field1,field2,field3) VALUES ('value1','value2','value3'); I have come up with the following PHP one-liner: mysql_query("INSERT INTO table (".implode(',',array_keys($_fields)).") VALUES (".implode(',',array_values($_fields)).")"); It separates the keys and values of the the associative array and implodes to generate a comma-separated string . The problem is that it does not escape or quote the values that were inserted into the database. To illustrate the danger, Imagine if $_fields contained the following: $_fields = array('field1'=>"naustyvalue); drop table members; --"); The following SQL would be generated: INSERT INTO table (field1) VALUES (naustyvalue); drop table members; --; Luckily, multiple queries are not supported, nevertheless quoting and escaping are essential to prevent SQL injection vulnerabilities. How do you write your PHP Mysql Inserts? Note: PDO or mysqli prepared queries aren't currently an option for me because the codebase already uses mysql extensively - a change is planned but it'd take alot of resources to convert?

    Read the article

  • How do you deal with naming conventions for rails partials?

    - by DJTripleThreat
    For example, I might have an partial something like: <div> <%= f.label :some_field %><br/> <%= f.text_field :some_field %> </div> which works for edit AND new actions. I also will have one like: <div> <%=h some_field %> </div> for the show action. So you would think that all your partials go under one directory like shared or something. The problem that I see with this is that both of these would cause a conflict since they are essentially the same partial but for different actions so what I do is: <!-- for edit and new actions --> <%= render "shared_edit/some_partial" ... %> <!-- for show action --> <%= render "shared_show/some_partial" ... %> How do you handle this? Is a good idea or even possible to maybe combine all of these actions into one partial and render different parts by determining what the current action is?

    Read the article

  • How to handle management trying to interfere with the project (including architecture decision)

    - by Zwei Steinen
    I feel this is not a very good question to post on SO, but I need some advice from experienced developers... (I'm a second year developer) I guess this is a problem to many, many projects, but in our case, it is getting intense. There were so much interference from people that don't know a bit about software development, that our development came to an almost complete stop. We had to literary escape to another location to get any useful job done. Now we were happily producing results, but then I get a request for a "meeting" and it's them again. I have a friendly relationship with them, but I feel very daunted at the thought of talking about non-sense all over again. Should I be firm and tell them to shut up and wait for our results? Or should I be diplomatic and create an illusion they are making a positive contribution or something?? My current urge is to be unfriendly and murmur some stuff so they will give up or something. What would you do if you were in this situation?

    Read the article

  • Facade controller, is it efficient?

    - by Berlioz
    Using a facade controller pattern in .net. It seems as if though it is not efficient BECAUSE, for every event that happens in a domain object(Sales, Register, Schedule, Car) it has to be subscribed to by the controller(use case controller) and then the controller in turn has to duplicate that same event to make it available for the presentation, so that the presentation can show it to the user. Does this make sense? Please comment!

    Read the article

< Previous Page | 142 143 144 145 146 147 148 149 150 151 152 153  | Next Page >