Search Results

Search found 40386 results on 1616 pages for 'object design'.

Page 417/1616 | < Previous Page | 413 414 415 416 417 418 419 420 421 422 423 424  | Next Page >

  • Better way to write an object generator for an RAII template class?

    - by Dan
    I would like to write an object generator for a templated RAII class -- basically a function template to construct an object using type deduction of parameters so the types don't have to be specified explicitly. The problem I foresee is that the helper function that takes care of type deduction for me is going to return the object by value, which will result in a premature call to the RAII destructor when the copy is made. Perhaps C++0x move semantics could help but that's not an option for me. Anyone seen this problem before and have a good solution? This is what I have: template<typename T, typename U, typename V> class FooAdder { private: typedef OtherThing<T, U, V> Thing; Thing &thing_; int a_; // many other members public: FooAdder(Thing &thing, int a); ~FooAdder(); void foo(T t, U u); void bar(V v); }; The gist is that OtherThing has a horrible interface, and FooAdder is supposed to make it easier to use. The intended use is roughly like this: FooAdder(myThing, 2) .foo(3, 4) .foo(5, 6) .bar(7) .foo(8, 9); The FooAdder constructor initializes some internal data structures. The foo and bar methods populate those data structures. The ~FooAdder dtor wraps things up and calls a method on thing_, taking care of all the nastiness. That would work fine if FooAdder wasn't a template. But since it is, I would need to put the types in, more like this: FooAdder<Abc, Def, Ghi>(myThing, 2) ... That's annoying, because the types can be inferred based on myThing. So I would prefer to create a templated object generator, similar to std::make_pair, that will do the type deduction for me. Something like this: template<typename T, typename U, typename V> FooAdder<T, U, V> AddFoo(Thing &thing, int a) { return FooAdder<T, U, V>(thing, a); } That seems problematic: because it returns by value, the stack temporary object will be destructed, which will cause the RAII dtor to run prematurely. One thought I had was to give FooAdder a copy ctor with move semantics, kinda like std::auto_ptr. But I would like to do this without dynamic memory allocation, so I thought the copy ctor could set a flag within FooAdder indicating the dtor shouldn't do the wrap-up. Like this: FooAdder(FooAdder &rhs) // Note: rhs is not const : thing_(rhs.thing_) , a_(rhs.a_) , // etc... lots of other members, annoying. , moved(false) { rhs.moved = true; } ~FooAdder() { if (!moved) { // do whatever it would have done } } Seems clunky. Anyone got a better way?

    Read the article

  • Entity Association Mapping with Code First Part 1 : Mapping Complex Types

    - by mortezam
    Last week the CTP5 build of the new Entity Framework Code First has been released by data team at Microsoft. Entity Framework Code-First provides a pretty powerful code-centric way to work with the databases. When it comes to associations, it brings ultimate flexibility. I’m a big fan of the EF Code First approach and am planning to explain association mapping with code first in a series of blog posts and this one is dedicated to Complex Types. If you are new to Code First approach, you can find a great walkthrough here. In order to build a solid foundation for our discussion, we will start by learning about some of the core concepts around the relationship mapping.   What is Mapping?Mapping is the act of determining how objects and their relationships are persisted in permanent data storage, in our case, relational databases. What is Relationship mapping?A mapping that describes how to persist a relationship (association, aggregation, or composition) between two or more objects. Types of RelationshipsThere are two categories of object relationships that we need to be concerned with when mapping associations. The first category is based on multiplicity and it includes three types: One-to-one relationships: This is a relationship where the maximums of each of its multiplicities is one. One-to-many relationships: Also known as a many-to-one relationship, this occurs when the maximum of one multiplicity is one and the other is greater than one. Many-to-many relationships: This is a relationship where the maximum of both multiplicities is greater than one. The second category is based on directionality and it contains two types: Uni-directional relationships: when an object knows about the object(s) it is related to but the other object(s) do not know of the original object. To put this in EF terminology, when a navigation property exists only on one of the association ends and not on the both. Bi-directional relationships: When the objects on both end of the relationship know of each other (i.e. a navigation property defined on both ends). How Object Relationships Are Implemented in POCO domain models?When the multiplicity is one (e.g. 0..1 or 1) the relationship is implemented by defining a navigation property that reference the other object (e.g. an Address property on User class). When the multiplicity is many (e.g. 0..*, 1..*) the relationship is implemented via an ICollection of the type of other object. How Relational Database Relationships Are Implemented? Relationships in relational databases are maintained through the use of Foreign Keys. A foreign key is a data attribute(s) that appears in one table and must be the primary key or other candidate key in another table. With a one-to-one relationship the foreign key needs to be implemented by one of the tables. To implement a one-to-many relationship we implement a foreign key from the “one table” to the “many table”. We could also choose to implement a one-to-many relationship via an associative table (aka Join table), effectively making it a many-to-many relationship. Introducing the ModelNow, let's review the model that we are going to use in order to implement Complex Type with Code First. It's a simple object model which consist of two classes: User and Address. Each user could have one billing address. The Address information of a User is modeled as a separate class as you can see in the UML model below: In object-modeling terms, this association is a kind of aggregation—a part-of relationship. Aggregation is a strong form of association; it has some additional semantics with regard to the lifecycle of objects. In this case, we have an even stronger form, composition, where the lifecycle of the part is fully dependent upon the lifecycle of the whole. Fine-grained domain models The motivation behind this design was to achieve Fine-grained domain models. In crude terms, fine-grained means “more classes than tables”. For example, a user may have both a billing address and a home address. In the database, you may have a single User table with the columns BillingStreet, BillingCity, and BillingPostalCode along with HomeStreet, HomeCity, and HomePostalCode. There are good reasons to use this somewhat denormalized relational model (performance, for one). In our object model, we can use the same approach, representing the two addresses as six string-valued properties of the User class. But it’s much better to model this using an Address class, where User has the BillingAddress and HomeAddress properties. This object model achieves improved cohesion and greater code reuse and is more understandable. Complex Types: Splitting a Table Across Multiple Types Back to our model, there is no difference between this composition and other weaker styles of association when it comes to the actual C# implementation. But in the context of ORM, there is a big difference: A composed class is often a candidate Complex Type. But C# has no concept of composition—a class or property can’t be marked as a composition. The only difference is the object identifier: a complex type has no individual identity (i.e. no AddressId defined on Address class) which make sense because when it comes to the database everything is going to be saved into one single table. How to implement a Complex Types with Code First Code First has a concept of Complex Type Discovery that works based on a set of Conventions. The convention is that if Code First discovers a class where a primary key cannot be inferred, and no primary key is registered through Data Annotations or the fluent API, then the type will be automatically registered as a complex type. Complex type detection also requires that the type does not have properties that reference entity types (i.e. all the properties must be scalar types) and is not referenced from a collection property on another type. Here is the implementation: public class User{    public int UserId { get; set; }    public string FirstName { get; set; }    public string LastName { get; set; }    public string Username { get; set; }    public Address Address { get; set; }} public class Address {     public string Street { get; set; }     public string City { get; set; }            public string PostalCode { get; set; }        }public class EntityMappingContext : DbContext {     public DbSet<User> Users { get; set; }        } With code first, this is all of the code we need to write to create a complex type, we do not need to configure any additional database schema mapping information through Data Annotations or the fluent API. Database SchemaThe mapping result for this object model is as follows: Limitations of this mappingThere are two important limitations to classes mapped as Complex Types: Shared references is not possible: The Address Complex Type doesn’t have its own database identity (primary key) and so can’t be referred to by any object other than the containing instance of User (e.g. a Shipping class that also needs to reference the same User Address). No elegant way to represent a null reference There is no elegant way to represent a null reference to an Address. When reading from database, EF Code First always initialize Address object even if values in all mapped columns of the complex type are null. This means that if you store a complex type object with all null property values, EF Code First returns a initialized complex type when the owning entity object is retrieved from the database. SummaryIn this post we learned about fine-grained domain models which complex type is just one example of it. Fine-grained is fully supported by EF Code First and is known as the most important requirement for a rich domain model. Complex type is usually the simplest way to represent one-to-one relationships and because the lifecycle is almost always dependent in such a case, it’s either an aggregation or a composition in UML. In the next posts we will revisit the same domain model and will learn about other ways to map a one-to-one association that does not have the limitations of the complex types. References ADO.NET team blog Mapping Objects to Relational Databases Java Persistence with Hibernate

    Read the article

  • Looking Back at MIX10

    - by WeigeltRo
    It’s the sad truth of my life that even though I’m fascinated by airplanes and flight in general since my childhood days, my body doesn’t like flying. Even the ridiculously short flights inside Germany are taking their toll on me each time. Now combine this with sitting in the cramped space of economy class for many hours on a transatlantic flight from Germany to Las Vegas and back, and factor in some heavy dose of jet lag (especially on my way eastwards), and you get an idea why after coming back home I had this question on my mind: Was it really worth it to attend MIX10? This of course is a question that will also be asked by my boss at Comma Soft (for other reasons, obviously), who decided to send me and my colleague Jens Schaller, to the MIX10 conference. (A note to my German readers: An dieser Stelle der Hinweis, dass Comma Soft noch Silverlight-Entwickler und/oder UI-Designer für den Standort Bonn sucht – aussagekräftige Bewerbungen bitte an [email protected]) Too keep things short: My answer is yes. Before I’ll go into detail, let me ask the heretical questions whether tech conferences in general still make sense. There was a time, where actually being at a tech conference gave you a head-start in regard to learning about new technologies. Nowadays this is no longer true, where every bit of information and every detail is immediately twittered, blogged and whatevered to death. In the case of MIX10 you even can download the video-taped sessions shortly after. So: Does visiting a conference still make sense? It depends on what you expect from a conference. It should be clear to everybody that you’ll neither get exclusive information, nor receive training in a small group. What a conference does offer that sitting in front of your computer does not can be summarized as follows: Focus Being away from work and home will help you to focus on the presented information. Of course there are always the poor guys who are haunted by their work (with mails and short text messages reporting the latest showstopper problem), but in general being out of your office makes a huge difference. Inspiration With the focus comes the emotional involvement. I find it much easier to absorb information if I feel that certain vibe when sitting in a session. This still means that I have put work into reviewing the information later, but it’s a better starting point. And all the impressions collected at a (good) conference combined lead to a higher motivation – be it by the buzz (“this is gonna be sooo cool!”) or by the fear to fall behind (“man, we’ll have work on this, or else…”). People At a conference it’s pretty easy to get into contact with other people during breakfast, lunch and other breaks. This is a good opportunity to get a feel for what other development teams are doing (on a very general level of course, nobody will tell you about their secret formula) and what they are thinking about specific technologies. So MIX10 did offer focus, inspiration and people, but that would have meant nothing without valuable content. When I (being a frontend developer with a strong interest in UI/UX) planned my visit to MIX10, I made the decision to focus on the "soft" topics of design, interaction and user experience. I figured that I would be bombarded with all the technical details about Silverlight 4 anyway in the weeks and months to come. Actually, I would have liked to catch a few technical sessions, but the agenda wasn’t exactly in favor of people interested in any kind of Silverlight and UI/UX/Design topics. That’s one of my few complaints about the conference – I would have liked one more day and/or more sessions per day. Overall, the quality of the workshops and sessions was pretty high. In fact, looking back at my collection of conferences I’ve visited in the past I’d say that MIX10 ranks somewhere near the top spot. Here’s an overview of the workshops/sessions I attended (I’ll leave out the keynotes): Day 0 (Workshops on Sunday) Design Fundamentals for Developers Robby Ingebretsen is the man! Great workshop in three parts with the perfect mix of examples, well-structured definition of terminology and the right dose of humor. Robby was part of the WPF team before founding his own company so he not only has a strong interest in design (and the skillz!) but also the technical background.   Design Tools and Techniques Originally announced to be held by Arturo Toledo, the Rosso brothers from ArcheType filled in for the first two parts, and Corrina Black had a pretty general part about the Windows Phone UI. The first two thirds were a mixed bag; the two guys definitely knew what they were talking about, and the demos were great, but the talk lacked the preparation and polish of a truly great presentation. Corrina was not allowed to go into too much detail before the keynote on Monday, but the session was still very interesting as it showed how much thought went into the Windows Phone UI (and there’s always a lot to learn when people talk about their thought process). Day 1 (Monday) Designing Rich Experiences for Data-Centric Applications I wonder whether there was ever a test-run for this session, but what Ken Azuma and Yoshihiro Saito delivered in the first 15 minutes of a 30-minutes-session made me walk out. A commercial for a product (just great: a video showing a SharePoint plug-in in an all-Japanese UI) combined with the most generic blah blah one could imagine. EPIC FAIL.   Great User Experiences: Seamlessly Blending Technology & Design I switched to this session from the one above but I guess I missed the interesting part – what I did catch was what looked like a “look at the cool stuff we did” without being helpful. Or maybe I was just in a bad mood after the other session.   The Art, Technology and Science of Reading This talk by Kevin Larson was very interesting, but was more a presentation of what Microsoft is doing in research (pretty impressive) and in the end lacked a bit the helpful advice one could have hoped for.   10 Ways to Attack a Design Problem and Come Out Winning Robby Ingebretsen again, and again a great mix of theory and practice. The clean and simple, yet effective, UI of the reader app resulted in a simultaneous “wow” of Jens and me. If you’d watch only one session video, this should be it. Microsoft has to bring Robby back next year! Day 2 (Tuesday) Touch in Public: Multi-touch Interaction Design for Kiosks & Architectural Experiences Very interesting session by Jason Brush, a great inspiration with many details to look out for in the examples. Exactly what I was hoping for – and then some!   Designing Bing: Heart and Science How hard can it be to design the UI for a search engine? An input field and a list of results, that should be it, right? Well, not so fast! The talk by Paul Ray showed the many iterations to finally get it right (up to the choice of a specific blue for the links). And yes, I want an eye-tracking device to play around with!   The Elephant in the Room When Nishant Kothary presented a long list of what his session was not about, I told to myself (not having the description text present) “Am I in the wrong talk? Should I leave?”. Boy, was I wrong. A great talk about human factors in the process of designing stuff.   An Hour with Bill Buxton Having seen Bill Buxton’s presentation in the keynote, I just had to see this man again – even though I didn’t know what to expect. Being more or less unplanned and intended to be more of a conversation, the session didn’t provide a wealth of immediately useful information. Nevertheless Bill Buxton was impressive with his huge knowledge of seemingly everything. But this could/should have been a session some when in the evening and not in parallel to at least two other interesting talks. Day 3 (Wednesday) Design the Ordinary, Like the Fixie This session by DL Byron and Kevin Tamura started really well and brought across the message to keep things simple. But towards the end the talk lost some of its steam. And, as a member of the audience pointed out, they kind of ignored their own advice when they used a fancy presentation software other then PowerPoint that sometimes got in the way of showing things.   Developing Natural User Interfaces Speaking of alternative presentation software, Joshua Blake definitely had the most remarkable alternative to PowerPoint, a self-written program called NaturalShow that was controlled using multi-touch on a touch screen. Not a PowerPoint-killer, but impressive nevertheless. The (excellent) talk itself was kind of eye-opening in regard to what “multi-touch support” on various platforms (WPF, Silverlight, Windows Phone) actually means.   Treat your Content Right The talk by Tiffani Jones Brown wasn’t even on my planned schedule, but somehow I ended up in that session – and it was great. And even for people who don’t necessarily have to write content for websites, some points made by Tiffani are valid in many places, notably wherever you put texts with more than a single word into your UI. Creating Effective Info Viz in Microsoft Silverlight The last session of MIX10 I attended was kind of disappointing. At first things were very promising, with Matthias Shapiro giving a brief but well-structured introduction to info graphics and interactive visualizations. Then the live-coding began and while the result was interesting, too much time was spend on wrestling to get the code working. Ending earlier than planned, the talk was a bit light on actual content, but at least it included a nice list of resources. Conclusion It could be felt all across MIX10, UIs will take a huge leap forward; in fact, there are enough examples that have already. People who both have the technical know-how and at least a basic understanding of design (“literacy” as Bill Buxton called it) are in high demand. The concept of the MIX conference and initiatives like design.toolbox shows that Microsoft understands very well that frontend developers have to acquire new knowledge besides knowing how to hack code and putting buttons on a form. There are extremely exciting times before us, with lots of opportunity for those who are eager to develop their skills, that is for sure.

    Read the article

  • Calculating a child Position, Rotation and Scale values?

    - by Sergio Plascencia
    I am making my own game editor(just for fun) anyway I have problem that I had several days trying to resolve but I have been unsuccessful. Here goes... I have an object "A": Position: (3,3,3), Rotation: (45,10,0), Scale(1,2,2.5) And an object "B": Position: (1,1,1), Rotation: (10,34,18), Scale(1.5,2,1) I now make a parent/child relationship. "B" is a child of "A": A |--B When I do the relationship I need to re-calculate the Child("B") Position, Rotation and Scale such that it maintains its current position, rotation and scale(Location in world). So for child position "B" it would now be (-2, -2, -2) since now "A" it is center and (-2, -2, -2) will keep the object in its same position. I think I got the Position and scale figure out, but rotation I cant. So I was trying to figure out what to do and what I did is opened Unity and run the same example and I did noticed that when making an abject a child object the child object did not moved at all but had its Position, Rotation and Scale values changed(Related to the parent). For example: Unity (Parent Object "A"): Position: (0,0,0) Rotation: (45,10,0) Scale: (1,1,1) Unity (Child Object "B"): Position: (0,0,0) Rotation: (0,0,0) Scale: (1,1,1) When making it a parent child relation("B" is a child of "A") the child object("B") in its Rotation values now has: X: -44.13605 Y: -14.00195 Z: 9.851074 If I plug the same values to my editor(To the child "B" rotation X, Y, Z values) the object does not move at all. So I basically need to know how did Unity arrive at those rotation values for the child(What are the calculations?). If you can help and put all the equations for the Position, Rotation or Scale then I can double check I am doing it correctly but with the Rotation I really need help. Thanks!

    Read the article

  • What are some good seminar topics that can be used to improve designer&developer communication?

    - by tactoth
    Hello guys the thing I'll tell is what happens in the company I work for but I know it's more like a common issue in software companies. I'm development team leader in a internet service company that provides service that's very similar to dropbox. In our company we have mainly two divisions: the tech division and the designers division, both have their own reporting hierarchy. Designers focus on designing UI and prioritizing features, while developers focus on implement designers' ideas (more like being driven as our big boss has said). Then here comes our issue: the DEV team and DES team communicate very bad. DEV complain DES for these reasons: Too frequent changing of requirements Too complicated interaction (our DEV team has actually learned many HCI principles) Documents for design are incomplete, usually you just get 'design principles' and it's up to DEV to complete design details. When you find design defects, you ask DES team to resolve them, then DES team quickly change the principles and you gonna spend another several weeks because the change is so fundamental. While DES complain DEV for these reasons: Code architecture is not good enough to adapt to changing requirements (Obviously DES knows something about software development) Product design is about principles, not details. DEV fails to realize this. Communication should be quick and should be mainly oral. Trying to make most feature discussion in document for reference is too overloaded and doesn't make sense. As you can see, DEV and DES have different ideas on product design, and encourages very different practice. We have this difference because of the way we work. So our solution is that we should plan some seminars to make each part more aware of the way the other part work. Then my question is, what are some good topics for such seminars? Guessing some people may not think seminars can solve this problem, please also suggest your solution.

    Read the article

  • BUILD 2013 Sessions&ndash;Building Great Windows Phone UI in XAML

    - by Tim Murphy
    Originally posted on: http://geekswithblogs.net/tmurphy/archive/2013/06/27/build-2013-sessionsndashbuilding-great-windows-phone-ui-in-xaml.aspx Even the simplest of smart phone apps can be a challenge to give a compelling UI regardless of the platform.  Windows Phone and XAML are no exception.  That is what got my interest in this session by Shawn Oster.  He took a checklist type approach to the subject is good considering that is about the only way that many us get things done. Shawn started out giving us a set of bad design/good design examples.  They very effectively showed how good design gives a sense of professionalism to your app that could determine if your wonderful idea actually makes money is DOA. I won’t go over all his points since you will be able to get the session online, but a few of his checklist points included design from the beginning instead of as an afterthought, not being afraid to leave white space and making sure your application elegantly supports both landscape and portrait modes.  The many gems make this a must watch for any developers who struggle with visual design. del.icio.us Tags: BUILD 2013,Windows Phone,XAML,Design

    Read the article

  • Is it OK to introduce methods that are used only during unit tests?

    - by Mchl
    Recently I was TDDing a factory method. The method was to create either a plain object, or an object wrapped in a decorator. The decorated object could be of one of several types all extending StrategyClass. In my test I wanted to check, if the class of returned object is as expected. That's easy when plain object os returned, but what to do when it's wrapped within a decorator? I code in PHP so I could use ext/Reflection to find out a class of wrapped object, but it seemed to me to be overcomplicating things, and somewhat agains rules of TDD. Instead I decided to introduce getClassName() that would return object's class name when called from StrategyClass. When called from the decorator however, it would return the value returned by the same method in decorated object. Some code to make it more clear: interface StrategyInterface { public function getClassName(); } abstract class StrategyClass implements StrategyInterface { public function getClassName() { return \get_class($this); } } abstract class StrategyDecorator implements StrategyInterface { private $decorated; public function __construct(StrategyClass $decorated) { $this->decorated = $decorated; } public function getClassName() { return $this->decorated->getClassName(); } } And a PHPUnit test /** * @dataProvider providerForTestGetStrategy * @param array $arguments * @param string $expected */ public function testGetStrategy($arguments, $expected) { $this->assertEquals( __NAMESPACE__.'\\'.$expected, $this->object->getStrategy($arguments)->getClassName() ) } //below there's another test to check if proper decorator is being used My point here is: is it OK to introduce such methods, that have no other use than to make unit tests easier? Somehow it doesn't feel right to me.

    Read the article

  • How to design a high-level application protocol for metadata syncing between devices and server?

    - by Jaanus
    I am looking for guidance on how to best think about designing a high-level application protocol to sync metadata between end-user devices and a server. My goal: the user can interact with the application data on any device, or on the web. The purpose of this protocol is to communicate changes made on one endpoint to other endpoints through the server, and ensure all devices maintain a consistent picture of the application data. If user makes changes on one device or on the web, the protocol will push data to the central repository, from where other devices can pull it. Some other design thoughts: I call it "metadata syncing" because the payloads will be quite small, in the form of object IDs and small metadata about those ID-s. When client endpoints retrieve new metadata over this protocol, they will fetch actual object data from an external source based on this metadata. Fetching the "real" object data is out of scope, I'm only talking about metadata syncing here. Using HTTP for transport and JSON for payload container. The question is basically about how to best design the JSON payload schema. I want this to be easy to implement and maintain on the web and across desktop and mobile devices. The best approach feels to be simple timer- or event-based HTTP request/response without any persistent channels. Also, you should not have a PhD to read it, and I want my spec to fit on 2 pages, not 200. Authentication and security are out of scope for this question: assume that the requests are secure and authenticated. The goal is eventual consistency of data on devices, it is not entirely realtime. For example, user can make changes on one device while being offline. When going online again, user would perform "sync" operation to push local changes and retrieve remote changes. Having said that, the protocol should support both of these modes of operation: Starting from scratch on a device, should be able to pull the whole metadata picture "sync as you go". When looking at the data on two devices side by side and making changes, should be easy to push those changes as short individual messages which the other device can receive near-realtime (subject to when it decides to contact server for sync). As a concrete example, you can think of Dropbox (it is not what I'm working on, but it helps to understand the model): on a range of devices, the user can manage a files and folders—move them around, create new ones, remove old ones etc. And in my context the "metadata" would be the file and folder structure, but not the actual file contents. And metadata fields would be something like file/folder name and time of modification (all devices should see the same time of modification). Another example is IMAP. I have not read the protocol, but my goals (minus actual message bodies) are the same. Feels like there are two grand approaches how this is done: transactional messages. Each change in the system is expressed as delta and endpoints communicate with those deltas. Example: DVCS changesets. REST: communicating the object graph as a whole or in part, without worrying so much about the individual atomic changes. What I would like in the answers: Is there anything important I left out above? Constraints, goals? What is some good background reading on this? (I realize this is what many computer science courses talk about at great length and detail... I am hoping to short-circuit it by looking at some crash course or nuggets.) What are some good examples of such protocols that I could model after, or even use out of box? (I mention Dropbox and IMAP above... I should probably read the IMAP RFC.)

    Read the article

  • How to create an XML document from a .NET object?

    - by JL
    I have the following variable that accepts a file name: var xtr = new XmlTextReader(xmlFileName) { WhitespaceHandling = WhitespaceHandling.None }; var xd = new XmlDocument(); xd.Load(xtr); I would like to change it so that I can pass in an object. I don't want to have to serialize the object to file first. Is this possible? Update: My original intentions were to take an xml document, merge some xslt (stored in a file), then output and return html... like this: public string TransformXml(string xmlFileName, string xslFileName) { var xtr = new XmlTextReader(xmlFileName) { WhitespaceHandling = WhitespaceHandling.None }; var xd = new XmlDocument(); xd.Load(xtr); var xslt = new System.Xml.Xsl.XslCompiledTransform(); xslt.Load(xslFileName); var stm = new MemoryStream(); xslt.Transform(xd, null, stm); stm.Position = 1; var sr = new StreamReader(stm); xtr.Close(); return sr.ReadToEnd(); } In the above code I am reading in the xml from a file. Now what I would like to do is just work with the object, before it was serialized to the file. So let me illustrate my problem using code public string TransformXMLFromObject(myObjType myobj , string xsltFileName) { // Notice the xslt stays the same. // Its in these next few lines that I can't figure out how to load the xml document (xd) from an object, and not from a file.... var xtr = new XmlTextReader(xmlFileName) { WhitespaceHandling = WhitespaceHandling.None }; var xd = new XmlDocument(); xd.Load(xtr); }

    Read the article

  • How can I programmatically add more than just one view object to my view controller?

    - by BeachRunnerJoe
    I'm diving into iPhone OS development and I'm trying to understand how I can add multiple view objects to the "Left/Root" view of my SplitView iPad app. I've figured out how to programmatically add a TableView to that view based on the example code I found in Apple's online documentation... RootViewController.h @interface RootViewController : UITableViewController <NSFetchedResultsControllerDelegate, UITableViewDelegate, UITableViewDataSource> { DetailViewController *detailViewController; UITableView *tableView; NSFetchedResultsController *fetchedResultsController; NSManagedObjectContext *managedObjectContext; } RootViewController.m - (void)loadView { UITableView *newTableView = [[UITableView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame] style:UITableViewStylePlain]; newTableView.autoresizingMask = UIViewAutoresizingFlexibleHeight|UIViewAutoresizingFlexibleWidth; newTableView.delegate = self; newTableView.dataSource = self; [newTableView reloadData]; self.view = newTableView; [newTableView release]; } but there are a few things I don't understand about it and I was hoping you veterans could help clear up some confusion. In the statement self.view = newTableView, I assume I'm setting the entire view to a single UITableView. If that's the case, then how can I add additional view objects to that view alongside the table view? For example, if I wanted to have a DatePicker view object and the TableView object instead of just the TableView object, then how would I programmatically add that? Referencing the code above, how can I resize the table view to make room for the DatePicker view object that I'd like to add? Thanks so much in advance for your help! I'm going to continue researching these questions right now.

    Read the article

  • In WMI, can I use a join (or something similar) to acquire the IisWebServer object for a site, given

    - by Precipitous
    Given a server name and a physical path, I'd like to be able to hunt down the IISWebServer object and ApplicationPool. Website url is also an acceptable input. Our technologies are IIS 6, WMI, and access via C# or Powershell 2. I'm certain this would be easier with IIS 7 its managed API. We don't have that yet. Here's what I can do: Get a list of IIS virtual directories from IISWebVirtualDirSetting and filter (offline) for the matching physical path. $theVirtualDir = gwmi -Namespace "root/MicrosoftIISv2" ` -ComputerName $servername -authentication PacketPrivacy ` -class "IISWebVirtualDirSetting" ` | where-object {$_.Path -like $deployLocation} From the virtual directory object, I can get a name (like W3SVC/40565456/root). Given this name, I can get to other goodies, such as the IIS web server object. gwmi -Namespace "root/MicrosoftIISv2" ` -ComputerName $servername ` -authentication PacketPrivacy ` -Query "SELECT * FROM IisWebServer WHERE Name='W3SVC/40589473'" The questions, restated: 1) This is a query language. Can I join or subquery so that 1 WMI query statement gets web servers based on IISWebVirtualDir.Path? How? 2) In solving 1, you'll have to explain how to query on the Path property. Why is this an invalid query? "SELECT * FROM IISWebVirtualDirSetting WHERE Path='D:\sites\globaldominator'"

    Read the article

  • Good practice to create extension methods that apply to System.Object?

    - by Christian
    Hello, I'm wondering whether I should create extension methods that apply on the object level or whether they should be located at a lower point in the class hierarchy. What I mean is something along the lines of: public static string SafeToString(this Object o) { if (o == null || o is System.DBNull) return ""; else { if (o is string) return (string)o; else return ""; } } public static int SafeToInt(this Object o) { if (o == null || o is System.DBNull) return 0; else { if (o.IsNumeric()) return Convert.ToInt32(o); else return 0; } } //same for double.. etc I wrote those methods since I have to deal a lot with database data (From the OleDbDataReader) that can be null (shouldn't, though) since the underlying database is unfortunately very liberal with columns that may be null. And to make my life a little easier, I came up with those extension methods. What I'd like to know is whether this is good style, acceptable style or bad style. I kinda have my worries about it since it kinda "pollutes" the Object-class. Thank you in advance & Best Regards :) Christian P.S. I didn't tag it as "subjective" intentionally.

    Read the article

  • ColdFusion 9 ORM - Securing an object at a low level...

    Hiya: I wonder if anybody has an idea on this... I'm looking at securing a low level object in my model (a "member" object) so by default only certain information can be accessed from it. Here's a possible approach (damn sexy if it would work!): 1) Add a property called "locked" - defaulting to "true" to the object itself. It appears that the only option to do this, and not tie it to a db table column, is to use the formula attribute that takes a query. So to default locked to TRUE I've got: <cfproperty name="locked" formula="select 1" /> 2) Then, I overwrite the existing set-ers and get-ers to use this: e.g. <cffunction name="getFullname" returnType="string"> <cfscript> if (this.getLocked()) { return this.getScreenName(); } else { return this.getFullname(); } </cfscript> </cffunction> 3) When i use it like this: <p> #oMember.getFullName()# </p> shows the ScreenName (great!) but... When I do this: <cfset oMember.setLocked(false)> <p> #oMember.getFullName()# </p> Just hangs!!! It appears that attempting to set a property that's been defined using "formula" is a no-no. Any ideas? Any other way we can have properties attached to an ORM object that are gettable and settable without them being present in the db? Ideas appreciated!

    Read the article

  • How can I bind Wpf DataGridColumn to an object?

    - by John
    I want to bind the columns of my WPF DataGrid to some objects in a Dictionary like this: Binding Path=Objects[i] where Objects is my Dictionary of objects, so that each cell will represent an Object element. How can I do that? I suppose that I need to create a template for my cell, which I did, but how to get the result of column binding in my template? I know that by default the content of a DataGridCell is a TextBlock and it's Text property is set through column binding result, but if that result is an object I guess that I have to create a ContentTemplate. How do I do that, as the stuff I tried is not displaying anything. Here it is what I tried: <Style x:Key="CellStyle" TargetType="{x:Type dg:DataGridCell}"> <Setter Property="Template"> ---it should realy be ContentTemplate? <Setter.Value> <ControlTemplate> <controls:DataGridCellControl CurrentObject="{Binding }"/> -- I would expect to get the object like this for this column path : Path=Objects[i] but is not working </ControlTemplate> </Setter.Value> </Setter> </Style> So, to make myself completly clear, i want to get in CurrentObject property of my DataGridCellControl the current object that should result if I set the column binding in my data grid like this Path=Objects[i]. Thank you for any suggestion, John.

    Read the article

  • Why won't WPF databindings show text when ToString() has a collaborating object?

    - by Jay
    In a simple form, I bind to a number of different objects -- some go in listboxes; some in textblocks. A couple of these objects have collaborating objects upon which the ToString() method calls when doing its work -- typically a formatter of some kind. When I step through the code I see that when the databinding is being set up, ToString() is called the collaborating object is not null and returns the expected result when inspected in the debugger, the objects return the expected result from ToString() BUT the text does not show up in the form. The only common thread I see is that these use a collaborating object, whereas the other bindings that show up as expected simply work from properties and methods of the containing object. If this is confusing, here is the gist in code: public class ThisThingWorks { private SomeObject some_object; public ThisThingWorks(SomeObject s) { some_object = s; } public override string ToString() { return some_object.name; } } public class ThisDoesntWork { private Formatter formatter; private SomeObject some_object; public ThisDoesntWork(SomeObject o, Formatter f) { formatter = f; some_object = o; } public override string ToString() { return formatter.Format(some_object.name); } } Again, let me reiterate -- the ToString() method works in every other context -- but when I bind to the object in WPF and expect it to display the result of ToString(), I get nothing. Update: The issue seems to be what I see as a buggy behaviour in the TextBlock binding. If I bind the Text property to a property of the DataContext that is declared as an interface type, ToString() is never called. If I change the property declaration to an implementation of the interface, it works as expected. Other controls, like Label work fine when binding the Content property to a DataContext property declared as either the implementation or the interface. Because this is so far removed from the title and content of this question, I've created a new question here: http://stackoverflow.com/questions/2917878/why-doesnt-textblock-databinding-call-tostring-on-a-property-whose-compile-tim

    Read the article

  • How can I pass in a params of Expression<Func<T, object>> to a method?

    - by Pure.Krome
    Hi folks, I have the following two methods :- public static IQueryable<T> IncludeAssociations<T>(this IQueryable<T> source, params string[] associations) { ... } public static IQueryable<T> IncludeAssociations<T>(this IQueryable<T> source, params Expression<Func<T, object>>[] expressions) { ... } Now, when I try and pass in a params of Expression<Func<T, object>>[], it always calls the first method (the string[]' and of course, that value isNULL`) Eg. Expression<Func<Order, object>> x1 = x => x.User; Expression<Func<Order, object>> x2 = x => x.User.Passport; var foo = _orderRepo .Find() .IncludeAssociations(new {x1, x2} ) .ToList(); Can anyone see what I've done wrong? Why is it thinking my params are a string? Can I force the type, of the 2x variables?

    Read the article

  • How to sum up a fetched result's number property based on the object's category?

    - by mr_kurrupt
    I have a NSFetchRequest that is returning all my saved objects (call them Items) and storing them in an NSMutableArray. Each of these Items have a category, an amount, and some other properties. My goal is to check the category of each Item and store the sum of the amounts for objects of the same category. So if I had these Items: Red; 10.00 Blue; 20.00 Green; 5.00 Red; 5.00 Green; 15.00 then I would have an array or other type of container than has: Red; 15.00 Blue; 20.00 Green; 20.00 What would be the best way to organize the data in such a manner? I was going to create a object class (call it Totals) that just has the category and amount. As I traverse through the fetch results in a for-loop, add Items with the same category in a Totals object an store them in a NSMutableArray. The problem I ran into with that is that I'm not sure how to check if an array contains a Totals object with a specific property. Specifically, a category that already exists. So if 'Red' exists, add the amount to it, otherwise create a new Totals object with category 'Red' and a the first Item's amount. Thanks.

    Read the article

  • Is locking on the requested object a bad idea?

    - by Quick Joe Smith
    Most advice on thread safety involves some variation of the following pattern: public class Thing { private static readonly object padlock = new object(); private string stuff, andNonsense; public string Stuff { get { lock (Thing.padlock) { if (this.stuff == null) this.stuff = "Threadsafe!"; } return this.stuff; } } public string AndNonsense { get { lock (Thing.padlock) { if (this.andNonsense == null) this.andNonsense = "Also threadsafe!"; } return this.andNonsense; } } // Rest of class... } In cases where the get operations are expensive and unrelated, a single locking object is unsuitable because a call to Stuff would block all calls to AndNonsense, degrading performance. And rather than create a lock object for each call, wouldn't it be better to acquire the lock on the member itself (assuming it is not something that implements SyncRoot or somesuch for that purpose? For example: public string Stuff { get { lock (this.stuff) { // Pretend that this is a very expensive operation. if (this.stuff == null) this.stuff = "Still threadsafe and good?"; } return this.stuff; } } Strangely, I have never seen this approach recommended or warned against. Am I missing something obvious?

    Read the article

  • chrome extension: get specific part of the current tab page in DOM object and display it in either popup.html or new html page?

    - by sandeep
    IS there any way so that i can convert any DOM object into HTML page within the script ? suppose I have dom object like this: content script.js chrome.extension.onRequest.addListener(function(request, sender, sendResponse) { if (request.method == "fromPopup") { console.log("got Request from Popup"); var myDivObj = document.getElementById("definition"); //sendResponse({data: "from Content Script to Popup"}); if ( myDivObj ) { sendResponse({data:myDivObj}); } else{ sendResponse({data:"Empty or No Tag"}); } console.log("sent Response1"); } else { sendResponse({}); // snub them. console.log("sent Response2"); } }); here is my popup.html <body> <Div>Searching..</Div> <Div id="output">Response??</Div> <script> console.log("Pop UP Clicked"); chrome.tabs.getSelected(null, function(tab) { chrome.tabs.sendRequest(tab.id, {method: "fromPopup", tabid: tab.id}, function(response) { console.log("got Response from Content Script"); document.getElementById("output").innerHTML=response.data; }); }); </script> </body> I know we can send onaly JSON type of data to the popup.html page.. am i right ? If yes is ther any way that I can creat HTML page with DOM Object( myDivObj ) which I collected.. Any alternative solution..? In short i want get only specific part of the current tab page in DOM object and display it in either popup.html or separate html page..

    Read the article

  • assembling an object graph without an ORM -- in the service layer or data layer?

    - by Hans Gruber
    At my current gig, our persistence layer uses IBatis going against SQL Server stored procedures (puke). IMHO, this approach has many disadvantages over the use of a "true" ORM such NHibernate or EF, but the one I'm trying to address here revolves around all the boilerplate code needed to map data from a result set into an object graph. Say I have the following DTO object graph I want to return to my presentation layer: IEnumerable<CustomerDTO> |--> IEnumerable<AddressDTO> |--> LatestOrderDTO The way I've implemented this is to have a discrete method in my DAO class to return each IEnumerable<*DTO>, and then have my service class be responsible for orchestrating the calls to the DAO. It then returns the fully assembled object graph to the client: public class SomeService(){ public SomeService(IDao someDao){ this._someDao = someDao; } public IEnumerable<CustomerDTO> ListCustomersForHistory(int brokerId){ var customers = _someDao.ListCustomersForBroker(brokerId); foreach (customer in customers){ customer.Addresses = someDao.ListCustomersAddresses(brokerId); customer.LatestOrder = someDao.GetCustomerLatestOrder(brokerId); } } return customers; } My question is should this logic belong in the service layer or the should I make my DAO such that it instead returns the assembled object graph. If I was using NHibernate, I assume that this kind of relationship association between objects comes for "free"?

    Read the article

  • Can I detect whether an object has called GC.SuppressFinalize?

    - by Joe White
    Is there a way to detect whether or not an object has called GC.SuppressFinalize? I have an object that looks something like this (full-blown Dispose pattern elided for clarity): public class ResourceWrapper { private readonly bool _ownsResource; private readonly UnmanagedResource _resource; public ResourceWrapper(UnmanagedResource resource, bool ownsResource) { _resource = resource; _ownsResource = ownsResource; if (!ownsResource) GC.SuppressFinalize(this); } ~ResourceWrapper() { if (_ownsResource) // clean up the unmanaged resource } } If the ownsResource constructor parameter is false, then the finalizer will have nothing to do -- so it seems reasonable (if a bit quirky) to call GC.SuppressFinalize right from the constructor. However, because this behavior is quirky, I'm very tempted to note it in an XML doc comment... and if I'm tempted to comment it, then I ought to write a unit test for it. But while System.GC has methods to set an object's finalizability (SuppressFinalize, ReRegisterForFinalize), I don't see any methods to get an object's finalizability. Is there any way to query whether GC.SuppressFinalize has been called on a given instance, short of buying Typemock or writing my own CLR host?

    Read the article

  • Pass object from JSON into MVC Controller - its always null ?

    - by SteveCl
    Hi I have seen a few questions on here related to the a similar issue, I have read them, followed them, but still i have the same problem. I am basically creating an object in javascript and trying to call a method on the controller that will return a string of html. Not JSON. I've been playing around with dataType and contentType but still no joy. So apologies if the code snippets are a bit messy. Build the object in JS. function GetCardModel() { var card = {}; card.CardTitle = $("#CardTitle").val(); card.TopicTitle = $("#TopicTitle").val(); card.TopicBody = $("#TopicBody").data("tEditor").value(); card.CardClose = $("#CardClose").val(); card.CardFromName = $("#CardFromName").val(); return card; } Take a look at the object - all looks good and as it should in JSON. var model = GetCardModel(); alert(JSON.stringify(GetCardModel())); Make the call... $.ajax({ type: "POST", url: "/Postcard/Create/Preview/", dataType: "json", //contentType: "application/json", date: GetCardModel(), processData: true, success: function (data) { alert("im back"); alert(data); }, error: function (xhr, ajaxOptions, error) { alert(xhr.status); alert("Error: " + xhr.responseText); //alert(error); } }); Always when I step into the controller, the object is ALWAYS there, but with null values for all the properties.

    Read the article

  • Can a PHP object respond to an undefined method?

    - by Nathan Long
    Rails relies on some of the neat aspects of Ruby. One of those is the ability to respond to an undefined method. Consider a relationship between Dog and Owner. Owner has_many :dogs and Dog belongs_to :owner. If you go into script/console, get a dog object with fido = Dog.find(1), and look at that object, you won't see a method or attribute called Owner. What you will see is an owner_id. And if you ask for fido.owner, the object will do something like this (at least, this is how it appears to me): I'm being asked for my .owner attribute. I don't have one of those! Before I throw a NoMethodError, do I have a rule about how to deal with this? Yes, I do: I should check and see if I have an owner_id. I do! OK, then I'll do a join and return that owner object. PHP's documentation is - ahem - a bit lacking sometimes, so I wonder if anyone here knows the answer to this: Can I define similar behavior for objects in PHP? If not, do you know of a workaround for flexible model joins like these?

    Read the article

  • Is there a way to deserialize an object into "$this"?

    - by Andreas Bonini
    I'm writing a class to handle a memcached object. The idea was to create abstract class Cachable and all the cachable objects (such as User, Post, etc) would be subclasses of said class. The class offers some method such as Load() which calls the abstract function LoadFromDB() if the object is not cached, functions to refresh/invalidate the cache, etc. The main problem is in Load(); I wanted to do something similar: protected function Load($id) { $this->memcacheId = $id; $this->Connect(); $cached = $this->memcache->get(get_class($this) . ':' . $id); if($cached === false) { $this->SetLoaded(LoadFromDB($id)); UpdateCache(); } else { $this = $cached; $this->SetLoaded(true); } } Unfortunately I need $this to become $cached (the cached object); is there any way to do that? Was the "every cachable object derives from the cachable class" a bad design idea?

    Read the article

  • XML Reader threw Object Null exception, but node exists(?!)

    - by Capt.Morgan
    I am hoping someone could enlighten me as to why I am getting the annoying - "xml object reference not set to an instance .." error. The elements (nodes?) I am looking for seem to exist and I have not misspelled it either :[ I might be doing something stupid here, but any help at all would be greatly appreciated. My Code: private void button1_Click(object sender, RoutedEventArgs e) { XmlDocument reader = new XmlDocument(); reader.Load("Kotaku - powered by FeedBurner.xml"); XmlNodeList titles = reader.GetElementsByTagName("title"); XmlNodeList dates = reader.GetElementsByTagName("pubDate"); XmlNodeList descriptions = reader.GetElementsByTagName("description"); XmlNodeList links = reader.GetElementsByTagName("link"); for (int i = 0; i < titles.Count; i++) { textBox1.AppendText(Environment.NewLine + titles[i].InnerText); textBox1.AppendText(Environment.NewLine + descriptions[i].InnerText); //<<-- Throws Object Ref Null Exception textBox1.AppendText(Environment.NewLine + links[i].InnerText); textBox1.AppendText(Environment.NewLine + dates[i].InnerText); //<<-- Throws Object Ref Null Exception } } The XML I am using is a saved XML page from: http://feeds.gawker.com/kotaku/full The way I am working on it now is as follows: I have saved the page from the above link (which is an XML page) and put it next to my EXE for easier access. Then I run the code.

    Read the article

< Previous Page | 413 414 415 416 417 418 419 420 421 422 423 424  | Next Page >