Search Results

Search found 3493 results on 140 pages for 'constructor'.

Page 90/140 | < Previous Page | 86 87 88 89 90 91 92 93 94 95 96 97  | Next Page >

• What is a good practice for handling SQL connections within a WCF call?

  - by Rising Star

  Suppose I want to create a (stateless) WCF service with three methods exposed on an endpoint: performSqlOperationA(), performSqlOperationB(), and performSqlOperationC(). Each method inserts data into a SQL database. The way I've seen things done at my office, each method would begin with code to initialize a SqlConnection object. Each method would end with code to safely dispose it. What is a good practice for coding these WCF methods so that the SqlConnection object is initialized and disposed in each method without having to do these things in each method? I know that I can have the connection initialized in the constructor for the class for the WCF methods, but I don't know about disposing it... The calls cannot be wrapped in a using block. One solution I'm familiar with is PostSharp, which allows me to set an attribute which causes specific code to automatically run at the beginning and end of each method call, but it would be greatly preferable to do this with only the .net framework.

  Read the article

• Java - Thread safety of ArrayList constructors

  - by andy boot

  I am looking at this piece of code. This constructor delegates to the native method "System.arraycopy" Is it Thread safe? And by that I mean can it ever throw a ConcurrentModificationException? public Collection<Object> getConnections(Collection<Object> someCollection) { return new ArrayList<Object>(someCollection); } Does it make any difference if the collection being copied is ThreadSafe eg a CopyOnWriteArrayList? public Collection<Object> getConnections(CopyOnWriteArrayList<Object> someCollection) { return new ArrayList<Object>(someCollection); }

  Read the article

• Parameter attributes in c#

  - by ng

  How can I do the following with c# attributes. Below is a snippet of Java that annotates parameters in a constructor. public class Factory { private final String name; private final String value; public Factory(@Inject("name") String name, @Inject("value") String value) { this.name = name; this.value = value; } } From looking at c# annotations it does not look like I can annotate parameters. Is this possible?

  Read the article

• Castle Windsor Weak Typed Factory

  - by JeffN825

  In a very very limited number of scenarios, I need to go from an unknown Type (at compile time) to an instance of the object registered for that type. For the most part, I use typed factories and I know the type I want to resolve at compile time...so I inject a Func<IMyType> into a constructor ...but in these limited number of scenarios, in order to avoid a direct call to the container (and thus having to reference Windsor from the library, which is an anti-pattern I'd like to avoid), I need to inject a Func<Type,object>...which I want to internally container.Resolve(type) for the Type parameter of the Func. Does anyone have some suggestions on the easiest/most straightforward way of setting this up? I tried the following, but with this setup, I end up bypassing the regular TypedFactoryFacility altogether which is definitely not what I want: Kernel.Register(Component.For(typeof (Func<Type, object>)).LifeStyle.Singleton.UsingFactoryMethod( (kernel, componentModel, creationContext) => kernel.Resolve(/* not sure what to put here... */))); Thanks in advance for any assistance.

  Read the article

• Create a class with array of objects.

  - by Bi

  Hi Code below defines a ChargeCustomer class that contains an array of type "customers". I want to be able to create an object with either 1 "customer" or 2 "customers" based on the constructor parameters. Is this the right way to do so in C#: public class ChargeCustomer { private Customer[] customers; public ChargeCustomer( string aName, string bName, int charge ) { customers = new Customer[2]; customers[0] = new Customer(aName, charge); customers[1] = new DropBox(bName, charge); } public ChargeCustomer( string bName, int charge ) { customers = new Customer[1]; customers[0] = new Customer( bName, charge ); } } Thanks!

  Read the article

• Freeing memory with Pointer Arithmetic

  - by Breedly

  C++ newb here. I'm trying to write my own implementation of an array using only pointers, and I've hit a wall I don't know how to get over. My constructor throws this error array.cpp:40:35: error: invalid conversion from ‘int*’ to ‘int’ [-fpermissive] When my array initializes I want it to free up all the spaces in the array for ints. Array::Array(int theSize){ size = theSize; int *arrayPointer = new int; int index = 0; while(theSize > index){ *(arrayPointer + index) = new int; //This is the trouble line. ++index; } } What am I doing wrong stackoverflow?

  Read the article

• silverlight adding single prism command delegate to a list of items in xaml

  - by bobwah

  I'm building a menu using Prism (using a trtelerik tree view with hierarchy data templates but hopefully the details don't matter) and I'm trying to set up a Click.Command on each menu items bindings that will all call the same delegate command which is defined in the view model. The menu is built up out of items which I don't really want to put any references to the command in. How do I bind the command to each of these items in xaml? I've looked around and it looks like in WPF I could use a relative source binding and find ancestors but there doesn't seem to be a way of doing this in silverlight. Can I setup the delegate as a static resource somehow? I don't think I can create a static resource to the view model as this uses Unity to resolve paramters to it's constructor.

  Read the article

• php class basic question

  - by Ross

  hi <?php class myClass { var $input; var $output; function myClass($input) { $output = 'You entered: ' . $input; return $output; } } $test = new myClass; echo $test->myClass(123); ?> this works, but returns this warning: Warning: Missing argument 1 for myClass::myClass() I read in to this, and seems that the constructor is expecting a value, so by adding: function myClass($input='') the warning is removed, but this seems so unnecessary? could someone enlighten me as to why it's required to define a value to prevent that warning? thanks for any pointers

  Read the article

• List in a Python class shares the same object over 2 different instances?

  - by zfranciscus

  I created a class: class A: aList = [] now I have function that instantiate this class and add items into the aList. note: there are 2 items for item in items: a = A(); a.aList.append(item); I find that the first A and the second A object has the same number of items in their aList. I would expect that the first A object will have the first item in its list and the second A object will have the second item in its aList. Can anyone explain how this happens ? PS: I manage to solve this problem by moving the aList inside a constructor : def __init__(self): self.aList = []; but I am still curious about this behavior

  Read the article

• WPF Prism deactivate ?

  - by 2Fast4YouBR

  Hi all, I have an problem and would like to know if it is common problem or jsut with me. I am using Wpf with Prism and Unity, all with the pattern MvvM. I am loading a viewModel that has a reference to a dropdown with few items, my idea is that each time that the user click in some place to open the view that has this dropdown is that the dropdown will be shown with diferent values. The problem is that I see is that after I show the view for the first time and after the first DEACTIVATE, when I try to load it again looks like it is already in the memory (was not deactivated/disposed), so as is already in memory, it not call the constructor again of the modelView and the dropdown is shown with tha same old values. public BranchSelectionViewModel(IUnityContainer unityContainer) { this.unityContainer = unityContainer; User user = this.unityContainer.Resolve<User>(); this.branches = new ObservableCollection<Department>(user.Departments .Where(department => department.DepartmentId != user.SelectedDepartment.DepartmentId)); }

  Read the article

• Understanding c++ block of code

  - by kotoko

  I was given a c++ main and have to code it so it works. I am having some trouble understanding the code as I am a bit new to cpp. Here is the code int main(int argc, char *argv[]) { Class::setAtribute("string"); Class(Class::CONSTANT) << "starting up..."; } Some questions: How can the first line work with no variables? Is it static? The second line is really strange for me, what I can make out is a Constructor that takes in a class constante and then prints it out somehow? If someone could explain me this bit of code it would be great! Thanks in advance.

  Read the article

• When (and why) is {} undefined in a JavaScript console?

  - by JS_Riddler

  In the console of both FF and Chrome, {} is considered undefined until explicitly evaluated: {}; // undefined ({}); // ? Object Actually, it's a bit less defined than undefined -- it's apparently bad syntax: {} === undefined; // SyntaxError: Unexpected token === {}.constructor; // SyntaxError: Unexpected token . But not if it's on the other side, in which case it's fine: "[object Object]" == {}.toString(); // true Or if it's not the first expression: undefined + undefined; // NaN {} + undefined; // NaN undefined + {}; // "undefined[object Object]" What gives?

  Read the article

• Does C++ require a destructor call for each placement new?

  - by Josh Haberman

  I understand that placement new calls are usually matched with explicit calls to the destructor. My question is: if I have no need for a destructor (no code to put there, and no member variables that have destructors) can I safely skip the explicit destructor call? Here is my use case: I want to write C++ bindings for a C API. In the C API many objects are accessible only by pointer. Instead of creating a wrapper object that contains a single pointer (which is wasteful and semantically confusing). I want to use placement new to construct an object at the address of the C object. The C++ object will do nothing in its constructor or destructor, and its methods will do nothing but delegate to the C methods. The C++ object will contain no virtual methods. I have two parts to this question. Is there any reason why this idea will not work in practice on any production compiler? Does this technically violate the C++ language spec?

  Read the article

• How to use SQLiteOpenHelper without or less restrictive use of Context?

  - by Pentium10

  If you extend SQLiteOpenHelper, for the Constructor you have to use a Context. I am wondering if there is a way to leave this out, and be able to work with database tables without a Context. Or at least be least restrictive, I mean a way of project/class structure that will make history the several context passings I have to do now. As it is my application has several level of classes, chained in each other, and there are a few that connects to the database, but have no whatsoever influence on the interface, so they don't actually need the Context. Are you creating your classes in the way that you pass each time a Context to them? If not, how you do, how you reuse a Context in a short class?

  Read the article

• Opinions about Dabo

  - by driverate

  Has anyone used Dabo lately? How does it rate vs Boa Constructor, etc? I'm writing a new Python database app and Dabo looks promising, but what's the real-world scoop on it? Is it used by many developers? It's not talked about very much here on SO, or anywhere, as far as I can tell. I'm just a little concerned that the support community might be too small, or the possibility that writers might decide to throw in the towel. What is your assessment of Dabo?

  Read the article

• Hidden Features of Google Guice

  - by Jon

  Google Guice provides some great dependency injection features. I came across the @Nullable feature recently which allows you to mark constructor arguments as optional (permitting null) since Guice does not permit these by default: e.g. public Person(String firstName, String lastName, @Nullable Phone phone) { this.firstName = checkNotNull(firstName, "firstName"); this.lastName = checkNotNull(lastName, "lastName"); this.phone = phone; } http://code.google.com/p/google-guice/wiki/UseNullable What are the other useful features of Guice (particularly the less obvious ones) that people use?

  Read the article

• Mask image does not appear on the screen

  - by Ponty

  I have imported to the library two images and have given them the custom class names MaskImage and MaskedImage. Then i write the code: package { import flash.display.*; public class MaskDemo extends Sprite { // Properties private var sprMaskedImage:Sprite; private var sprMaskImage:Sprite; private var bmMaskedImage:Bitmap; private var bmMaskImage:Bitmap; // Constructor public function MaskDemo() { do_magic(); } // Methods private function do_magic():void { bmMaskedImage = new Bitmap(new MaskedImage(0, 0)); bmMaskImage = new Bitmap(new MaskImage(0, 0)); sprMaskedImage = new Sprite(); sprMaskedImage.addChild(bmMaskedImage); sprMaskImage = new Sprite(); sprMaskImage.addChild(bmMaskImage); sprMaskedImage.mask = sprMaskImage; this.addChild(sprMaskImage); } } } But it does not appear anything on the display. Any ideas why is happening that?

  Read the article

• C++ allocate objects on heap of base class with protected constructors via inheritance

  - by KRao

  I have a class with protected constructor: class B { protected: B(){}; }; Now I derive from it and define two static functions and I manage to actually create objects of the class B, but not on the heap: class A : public B { public: static B createOnStack() {return B();} //static B* createOnHeap() {return new B;} //Compile time Error on VS2010 }; B b = A::createOnStack(); //This works on VS2010! The question is: 1) Is VS2010 wrong in allowing the first case? 2) Is it possible to create objects of B without modifying B in any way (no friendship and no extra functions). I am asking, because it is possible to make something similar when dealing with instances of B and its member functions, see: http://accu.org/index.php/journals/296 Thank you in advance for any suggestion! Kind regards

  Read the article

• Usage patterns/use cases for DI or when to start using it

  - by Fabian

  I'm not sure for which use cases one should to use DI in the application. I know that injecting services like PlaceService or CalculationService etc fits very well but should I also create my domain objects with DI like a User? What is if the User has only one constructor which requires a first and lastname. Is this solveable with DI? Should I use DI to create the instances for Set/List interfaces or is this pure overkill? I use guice primarily.

  Read the article

• how to get TabHeader on trigger

  - by CurlyFro

  i have a tabcontrol. i'm trying to pass the tabcontrol as a parameter to figure out the selected tab item so i can get the tab header name. Binding this doesn't seem to work. ideas? <TabControl Background="#FFF9F9F9" Height="650"> <i:Interaction.Triggers> <i:EventTrigger EventName="SelectionChanged"> <n:ExecuteCommandAction Command="{Binding UpdateTabCommand}" Parameter="{Binding this}"/> </i:EventTrigger> </i:Interaction.Triggers> in my viewmodel constructor i have: _updateTabCommand = new ActionCommand< TabControl>(UpdateTab); private method: public void UpdateTab(TabControl tabControl) { var tabItem = (TabItem)tabControl.SelectedItem;

  Read the article

• Want to understand C++ sentry object

  - by Romain Hippeau

  I answered this [question][1] and somebody else had answered as he modern C++ equivalent would be a sentry object: construct it at the beginning of a function, with its constructor implementing call(), and upon return (or abnormal exit), its destructor implements I am not familiar with using sentry objects in C++. I thought they were limited to input and output streams. Could somebody explain to me about C++ sentry objects as well as how to use them as an around interceptor for one or more methods in a class ? [1]: http://stackoverflow.com/questions/2688043/call-return-feature-of-classic-cc-with-classes-what-modern-languages-have-it/2688095#2688095 /

  Read the article

• Can I use Linq to project a new typed datarow?

  - by itchi

  I currently have a csv file that I'm parsing with an example from here: http://alexreg.wordpress.com/2009/05/03/strongly-typed-csv-reader-in-c/ I then want to loop the records and insert them using a typed dataset xsd to an Oracle database. It's not that difficult, something like: foreach (var csvItem in csvfile) { DataSet.MYTABLEDataTable DT = new DataSet.MYTABLEDataTable(); DataSet.MYTABLERow row = DT.NewMYTABLERow(); row.FIELD1 = csvItem.FIELD1; row.FIELD2 = csvItem.FIELD2; } I was wondering how I would do something with LINQ projection: var test = from csvItem in csvfile select new MYTABLERow { FIELD1 = csvItem.FIELD1, FIELD2 = csvItem.FIELD2 } But I don't think I can create datarows like this without the use of a rowbuilder, or maybe a better constructor for the datarow?

  Read the article

• Getting list of fields back from 'use fields' pragma?

  - by makenai

  So I'm familiar with the use fields pragma in Perl that can be used to restrict the fields that are stored in a class: package Fruit; use fields qw( color shape taste ); sub new { my ( $class, $params ) = @_; my $self = fields::new( $class ) unless ref $class; foreach my $name ( keys %$params ) { $self->{ $name } = $params->{ $name }; } return $self; } My question is.. once I've declared the fields at the top, how I can get the list back.. say because I want to generate accessors dynamically? Is keys %FIELDS the only way? Secondarily, is there a more efficient way to pre-populate the fields in the constructor than looping through and assigning each parameter as I am above? Thanks!

  Read the article

• How can I customize the title bar on JFrame?

  - by Jonas

  I would like to have a customized title bar in my Java Swing desktop application. What is the best way to do that? I can use a "Swing-title bar" by using the following code in the constructor for my JFrame: this.setUndecorated(true); this.getRootPane().setWindowDecorationStyle(JRootPane.FRAME); But how do I customize it? Is there any UI delegates that I can override or do I have to implement my own title bar from scratch? I want something like Lawson Smart Office: Or like Trend Micro Internet Security:

  Read the article

• How to initialise an array inside a struct without doing each element separately? (C++)

  - by Janet

  My questions are in the code, but basically i want to know how/if I can do the two commented out lines? I know I can do it in a constructor but I don't want to! struct foo { int b[4]; } boo; //boo.b[] = {7, 6, 5, 4}; // <- why doesn't this work? (syntax error : ']') //boo.b = {7, 6, 5, 4}; // <- or else this? (syntax error : '{') boo.b[0] = 7; // <- doing it this way is annoying boo.b[1] = 6; // : boo.b[2] = 5; // : boo.b[3] = 4; // <- doing it this way is annoying boo.b[4] = 3; // <- why does this work! (Using: C++, Visual Studio 2005.)

  Read the article

< Previous Page | 86 87 88 89 90 91 92 93 94 95 96 97  | Next Page >