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  • Need to cast to an object without knowing what type the object is

    - by jle
    I am trying to dynamically load my authentication server type based on a setting. I am hung up on how to cast to a type when I don't know the type. Type t = Type.GetType(WebConfigurationManager.AppSettings.Get("AuthenticationSvcImpl")); IAuthenticationService authCli = Activator.CreateInstance(t); return authCli.AuthenticateUser(login); I know there is Convert.ChangeType(), but that just converts to an object...

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  • Javascript: how to access anonymous object within object?

    - by Caballero
    I have a string generated by php's json_encode() that looks like this: [ { "key1":"value1", "key2":"value2", "key3":"value3" }, { "key1":"value1", "key2":"value2", "key3":"value3" } ] I use Javascript function to convert the string to Javascript object: var jsonObj=JSON.parse(string); How do I access the data inside since the inner objects have no names? I tried something like: alert(jsonObj.firstChild.key1); It gives me "undefined". Why is that so?

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  • How to create multiple Repository object inside a Repository class using Unit Of Work?

    - by Santosh
    I am newbie to MVC3 application development, currently, we need following Application technologies as requirement MVC3 framework IOC framework – Autofac to manage object creation dynamically Moq – Unit testing Entity Framework Repository and Unit Of Work Pattern of Model class I have gone through many article to explore an basic idea about the above points but still I am little bit confused on the “Repository and Unit Of Work Pattern “. Basically what I understand Unit Of Work is a pattern which will be followed along with Repository Pattern in order to share the single DB Context among all Repository object, So here is my design : IUnitOfWork.cs public interface IUnitOfWork : IDisposable { IPermitRepository Permit_Repository{ get; } IRebateRepository Rebate_Repository { get; } IBuildingTypeRepository BuildingType_Repository { get; } IEEProjectRepository EEProject_Repository { get; } IRebateLookupRepository RebateLookup_Repository { get; } IEEProjectTypeRepository EEProjectType_Repository { get; } void Save(); } UnitOfWork.cs public class UnitOfWork : IUnitOfWork { #region Private Members private readonly CEEPMSEntities context = new CEEPMSEntities(); private IPermitRepository permit_Repository; private IRebateRepository rebate_Repository; private IBuildingTypeRepository buildingType_Repository; private IEEProjectRepository eeProject_Repository; private IRebateLookupRepository rebateLookup_Repository; private IEEProjectTypeRepository eeProjectType_Repository; #endregion #region IUnitOfWork Implemenation public IPermitRepository Permit_Repository { get { if (this.permit_Repository == null) { this.permit_Repository = new PermitRepository(context); } return permit_Repository; } } public IRebateRepository Rebate_Repository { get { if (this.rebate_Repository == null) { this.rebate_Repository = new RebateRepository(context); } return rebate_Repository; } } } PermitRepository .cs public class PermitRepository : IPermitRepository { #region Private Members private CEEPMSEntities objectContext = null; private IObjectSet<Permit> objectSet = null; #endregion #region Constructors public PermitRepository() { } public PermitRepository(CEEPMSEntities _objectContext) { this.objectContext = _objectContext; this.objectSet = objectContext.CreateObjectSet<Permit>(); } #endregion public IEnumerable<RebateViewModel> GetRebatesByPermitId(int _permitId) { // need to implment } } PermitController .cs public class PermitController : Controller { #region Private Members IUnitOfWork CEEPMSContext = null; #endregion #region Constructors public PermitController(IUnitOfWork _CEEPMSContext) { if (_CEEPMSContext == null) { throw new ArgumentNullException("Object can not be null"); } CEEPMSContext = _CEEPMSContext; } #endregion } So here I am wondering how to generate a new Repository for example “TestRepository.cs” using same pattern where I can create more then one Repository object like RebateRepository rebateRepo = new RebateRepository () AddressRepository addressRepo = new AddressRepository() because , what ever Repository object I want to create I need an object of UnitOfWork first as implmented in the PermitController class. So if I would follow the same in each individual Repository class that would again break the priciple of Unit Of Work and create multiple instance of object context. So any idea or suggestion will be highly appreciated. Thank you

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  • How to get exactly typeof is object/array/null..?

    - by 3gwebtrain
    var obj = {},ar = [],nothing=null,empty=undefined,word ='string',headorTail = true; console.log(typeof obj) //object console.log(typeof ar)//object console.log(typeof nothing)//object console.log(typeof empty)//undefined console.log(typeof word)//string console.log(typeof headorTail)//boolean But how can i get the type of obj,ar,nothing as "object, array,null" - what is the best way to achieve this?

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  • state: pending & public-address: null :: Juju setup on local machine

    - by Danny Kopping
    I've setup Juju on a local VM inside VMWare running on Mac OSX. Everything seems to be working fine, except when I deployed MySQL & WordPress from the examples, I get the following when I run juju status: danny@ubuntu:~$ juju status machines: 0: dns-name: localhost instance-id: local instance-state: running state: down services: mysql: charm: local:oneiric/mysql-11 relations: db: wordpress units: mysql/0: machine: 0 public-address: 192.168.122.107 relations: db: state: up state: started wordpress: charm: local:oneiric/wordpress-31 exposed: true relations: db: mysql units: wordpress/0: machine: 0 open-ports: [] public-address: null relations: {} state: pending state: pending and public-address: null Can't find any documentation relating to this issue. Any help very much appreciated - wonderful idea for a project!

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  • SpriteBatch.end() generating null pointer exception

    - by odaymichael
    I am getting a null pointer exception using libGDX that the debugger points as the SpriteBatch.end() line. I was wondering what would cause this. Here is the offending code block, specifically the batch.end() line: batch.begin(); for (int j = 0; j < 3; j++) for (int i = 0; i < 3; i++) if (zoomgrid[i][j].getPiece().getImage() != null) zoomgrid[i][j].getPiece().getImage().draw(batch); batch.end(); The top of the stack is actually a line that calls lastTexture.bind(); In the flush() method of com.badlogic.gdx.graphics.g2d.SpriteBatch. I appreciate any input, let me know if I haven't included enough information.

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  • How does throwing an ArgumentNullException help?

    - by Scott Whitlock
    Let's say I have a method: public void DoSomething(ISomeInterface someObject) { if(someObject == null) throw new ArgumentNullException("someObject"); someObject.DoThisOrThat(); } I've been trained to believe that throwing the ArgumentNullException is "correct" but an "Object reference not set to an instance of an object" error means I have a bug. Why? I know that if I was caching the reference to someObject and using it later, then it's better to check for nullity when passed in, and fail early. However, if I'm dereferencing it on the next line, why are we supposed to do the check? It's going to throw an exception one way or the other. Edit: It just occurred to me... does the fear of the dereferenced null come from a language like C++ that doesn't check for you (i.e. it just tries to execute some method at memory location zero + method offset)?

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  • What does /dev/null mean in the shell?

    - by rishiag
    I've started learning bash scripting by using this guide: http://www.tldp.org/LDP/abs/abs-guide.pdf However I got stuck at the first script: cd /var/log cat /dev/null > messages cat /dev/null > wtmp echo "Log files cleaned up." What do lines 2 and 3 do in Ubuntu (I understand cat)? Is it only for other Linux distributions? After running this script as root, the output I get is Log files cleaned up. But /var/log still contains all the files.

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  • Object array updates one instance repeatedly [on hold]

    - by MGN001
    I'm making a 2D shooter, and the player object holds an array of bullets that represent how many shots the player can have on screen at once. At least, this is what I'm trying for. What's happening is that each time any of the objects in the array is called, it seems to update a single object in memory. So, if I fire and then fire again, the object "starts over" from where I shot from and moves twice as fast. I've spent weeks trying to fix this and I've managed nothing. Hopefully another pair of eyes will see something I've missed. Player.cpp #include "Player.h" const int startLives = 3; const int maxHealth = 2; const float speed = 1; const int maxVelocity = 500; const int topBound = WINDOW_HEIGHT / 5 * 3; const int slowRate = 500; const int accRate = 1000; const int maxBullets = 5; const float spriteWidth = 99; const float spriteHeight = 75; const Vector2f startPosition = { (WINDOW_WIDTH / 2) - (spriteWidth / 2), (WINDOW_HEIGHT / 4 * 3) - (spriteHeight / 2) }; Bullet bullets[maxBullets]; Bullet * bulletPointers[maxBullets]; SDL_Texture * playerHealthy; SDL_Texture * playerDamaged; SDL_Texture * currentSprite; SDL_Rect * rect; Vector2f position; Vector2f velocity; int Health; int Lives; Player::Player() { rect = new SDL_Rect(); } Player::~Player() { SDL_DestroyTexture(playerHealthy); SDL_DestroyTexture(playerDamaged); SDL_DestroyTexture(currentSprite); rect = NULL; } void Player::Initialize(SDL_Renderer * renderer) { SDL_Surface * temp; temp = IMG_Load(".\\Sprites\\player.png"); if (temp == NULL) { printf("Initialization Error: %s\n", IMG_GetError()); exit(PLAYER_INITIALIZATION_ERROR); } playerHealthy = SDL_CreateTextureFromSurface(renderer, temp); temp = IMG_Load(".\\Sprites\\playerDamaged.png"); if (temp == NULL) { printf("Initialization Error: %s\n", IMG_GetError()); exit(PLAYER_INITIALIZATION_ERROR); } playerDamaged = SDL_CreateTextureFromSurface(renderer, temp); temp = IMG_Load(".\\Sprites\\laserGreen.png"); if (temp == NULL) { printf("Initialization Error: %s\n", IMG_GetError()); exit(PLAYER_INITIALIZATION_ERROR); } SDL_Texture * bullet = SDL_CreateTextureFromSurface(renderer, temp); temp = IMG_Load(".\\Sprites\\laserGreenShot.png"); if (temp == NULL) { printf("Initialization Error: %s\n", IMG_GetError()); exit(PLAYER_INITIALIZATION_ERROR); } SDL_Texture * explosion = SDL_CreateTextureFromSurface(renderer, temp); for (int i = 0; i < maxBullets; i++) { bullets[i].Initialize(renderer, bullet, explosion); bulletPointers[i] = NULL; } temp = NULL; rect->h = spriteHeight; rect->w = spriteWidth; Reset(); } void Player::Update(Input input, float deltaTime) { if (abs(velocity.x) < slowRate * deltaTime) { velocity.x = 0; } else if (velocity.x > 0) { velocity.x -= slowRate * deltaTime; } else if (velocity.x < 0) { velocity.x += slowRate * deltaTime; } if (abs(velocity.y) < slowRate * deltaTime) { velocity.y = 0; } if (velocity.y > 0) { velocity.y -= slowRate * deltaTime; } else if (velocity.y < 0) { velocity.y += slowRate * deltaTime; } if (Health <= 0) { --Lives; Spawn(); } velocity.x += UnitVector(input.InputNew.movement).x * accRate * deltaTime; velocity.y += UnitVector(input.InputNew.movement).y * accRate * deltaTime; if (Magnitude(velocity) > maxVelocity) { velocity.x = UnitVector(velocity).x * maxVelocity; velocity.y = UnitVector(velocity).y * maxVelocity; } position.x += velocity.x * deltaTime * speed; position.y += velocity.y * deltaTime * speed; if (input.InputNew.JumpLeft && !input.InputOld.JumpLeft) { position.x -= spriteWidth; } if (input.InputNew.JumpRight && !input.InputOld.JumpRight) { position.x += spriteWidth; } Boundaries(); rect->x = position.x; rect->y = position.y; if (input.InputNew.Fire && !input.InputOld.Fire) { Fire(); } for (int i = 0; i < maxBullets; ++i) { if (bulletPointers[i] != NULL) { bullets[i].Update(deltaTime); if (bullets[i].getPosition().y < -33) { bulletPointers[i] = NULL; } } } } void Player::Draw(SDL_Renderer * renderer) { for (int i = 0; i < maxBullets; ++i) { if (bulletPointers[i] != NULL) { bullets[i].Draw(renderer); } } SDL_RenderCopy(renderer, currentSprite, NULL, rect); } void Player::Spawn() { position = startPosition; Health = maxHealth; currentSprite = playerHealthy; rect->x = position.x; rect->y = position.y; } void Player::Boundaries() { if (position.x < 0) { position.x = 0; velocity.x *= -1; } else if (position.x > WINDOW_WIDTH - spriteWidth) { position.x = WINDOW_WIDTH - spriteWidth; velocity.x *= -1; } if (position.y < topBound) { position.y = topBound; velocity.y *= -1; } else if (position.y > WINDOW_HEIGHT - spriteHeight) { position.y = WINDOW_HEIGHT - spriteHeight; velocity.y *= -1; } } int Player::getLives() { return Lives; } void Player::Reset() { Lives = startLives; Spawn(); } void Player::Fire() { for (int i = 0; i < maxBullets; ++i) { if (bulletPointers[i] == NULL) { bulletPointers[i] = &bullets[i]; bullets[i].Fire(position,velocity.x/2); break; } } } Bullet.cpp #include "Bullet.h" const int speed = 500; Vector2f bulletVelocity; float ExplosionMax = 0.5f; float ExplosionTimer; const Vector2f fireOffset = { 45.5f, 10.0f }; const Vector2f explosionOffset = { 23.5f, -27.0f }; const Vector2i bulletSize = { 9, 33 }; const Vector2i explosionSize = { 56, 54 }; Vector2f bulletPosition; SDL_Texture * bulletSprite; SDL_Texture * explosionSprite; SDL_Texture * bulletCurrentSprite; SDL_Rect * bulletRect; Bullet::Bullet() { } Bullet::~Bullet() { } void Bullet::Initialize(SDL_Renderer * renderer, SDL_Texture * bullet, SDL_Texture * explosion) { bulletSprite = bullet; explosionSprite = explosion; bulletRect = new SDL_Rect(); } void Bullet::Update(float deltaTime) { bulletPosition.y -= bulletVelocity.y * deltaTime; bulletPosition.x += bulletVelocity.x * deltaTime; bulletRect->x = static_cast<int>(bulletPosition.x); bulletRect->y = static_cast<int>(bulletPosition.y); } void Bullet::Draw(SDL_Renderer * renderer) { SDL_RenderCopy(renderer, bulletCurrentSprite, NULL, bulletRect); } void Bullet::Fire(Vector2f pos, float xSpeed) { bulletPosition.x = pos.x + fireOffset.x; bulletPosition.y = pos.y + fireOffset.y; bulletVelocity.x = xSpeed; bulletVelocity.y = speed; bulletCurrentSprite = bulletSprite; bulletRect->h = bulletSize.y; bulletRect->w = bulletSize.x; bulletRect->x = static_cast<int>(bulletPosition.x); bulletRect->y = static_cast<int>(bulletPosition.y); } Vector2f Bullet::getPosition() { return bulletPosition; } void Bullet::Hit() { bulletCurrentSprite = explosionSprite; bulletVelocity = { 0.0f, 0.0f }; ExplosionTimer = ExplosionMax; bulletPosition.x += explosionOffset.x; bulletPosition.y += explosionOffset.y; bulletRect->w = explosionSize.x; bulletRect->h = explosionSize.y; }

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  • Falsey values vs null, undefned, or empty string

    - by user687554
    I've worked with jQuery over the years. However, recently, I've found myself getting deeper into the JavaScript language. Recently, I've heard about "truthy" and falsey values. However, I don't fully understand them. Currently, I have some code that looks like this: var fields = options.fields || ['id', 'query']; I need to identify if fields is null, undefined, or has a length of 0. I know the long way is to do: if ((fields === null) || (fields === undefined) || (fields.length === 0)) { ... } My question is, is the following the same: if (!fields) { ... } Thank you!

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  • MySQL ignores the NOT NULL constraint

    - by Marga Keuvelaar
    I have created a table with NOT NULL constraints on some columns in MySQL. Then in PHP I wrote a script to insert data, with an insert query. When I omit one of the NOT NULL columns in this insert statement I would expect an error message from MySQL, and I would expect my script to fail. Instead, MySQL inserts empty strings in the NOT NULL fields. In other omitted fields the data is NULL, which is fine. Could someone tell me what I did wrong here? I'm using this table: CREATE TABLE IF NOT EXISTS tblCustomers ( cust_id int(11) NOT NULL AUTO_INCREMENT, custname varchar(50) NOT NULL, company varchar(50), phone varchar(50), email varchar(50) NOT NULL, country varchar(50) NOT NULL, ... date_added timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP, PRIMARY KEY (cust_id) ) ; And this insert statement: $sql = "INSERT INTO tblCustomers (custname,company) VALUES ('".$customerName."','".$_POST["CustomerCompany"]."')"; $res = mysqli_query($mysqli, $sql);

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  • mysql ignores not null constraint?

    - by Marga Keuvelaar
    I have created a table with NOT NULL constraints on some columns in MySQL. Then in PHP I wrote a script to insert data, with an insert query. When I omit one of the NOT NULL columns in this insert statement I would expect an error message from MySQL, and I would expect my script to fail. Instead, MySQL inserts empty strings in the NOT NULL fields. In other omitted fields the data is NULL, which is fine. Could someone tell me what I did wrong here? I'm using this table: CREATE TABLE IF NOT EXISTS tblCustomers ( cust_id int(11) NOT NULL AUTO_INCREMENT, custname varchar(50) NOT NULL, company varchar(50), phone varchar(50), email varchar(50) NOT NULL, country varchar(50) NOT NULL, ... date_added timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP, PRIMARY KEY (cust_id) ) ; And this insert statement: $sql = "INSERT INTO tblCustomers (custname,company) VALUES ('".$customerName."','".$_POST["CustomerCompany"]."')"; $res = mysqli_query($mysqli, $sql);

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  • PHP OOP: Avoid Singleton/Static Methods in Domain Model Pattern

    - by sunwukung
    I understand the importance of Dependency Injection and its role in Unit testing, which is why the following issue is giving me pause: One area where I struggle not to use the Singleton is the Identity Map/Unit of Work pattern (Which keeps tabs on Domain Object state). //Not actual code, but it should demonstrate the point class Monitor{//singleton construction omitted for brevity static $members = array();//keeps record of all objects static $dirty = array();//keeps record of all modified objects static $clean = array();//keeps record of all clean objects } class Mapper{//queries database, maps values to object fields public function find($id){ if(isset(Monitor::members[$id]){ return Monitor::members[$id]; } $values = $this->selectStmt($id); //field mapping process omitted for brevity $Object = new Object($values); Monitor::new[$id]=$Object return $Object; } $User = $UserMapper->find(1);//domain object is registered in Id Map $User->changePropertyX();//object is marked "dirty" in UoW // at this point, I can save by passing the Domain Object back to the Mapper $UserMapper->save($User);//object is marked clean in UoW //but a nicer API would be something like this $User->save(); //but if I want to do this - it has to make a call to the mapper/db somehow $User->getBlogPosts(); //or else have to generate specific collection/object graphing methods in the mapper $UserPosts = $UserMapper->getBlogPosts(); $User->setPosts($UserPosts); Any advice on how you might handle this situation? I would be loathe to pass/generate instances of the mapper/database access into the Domain Object itself to satisfy DI - At the same time, avoiding that results in lots of calls within the Domain Object to external static methods. Although I guess if I want "save" to be part of its behaviour then a facility to do so is required in its construction. Perhaps it's a problem with responsibility, the Domain Object shouldn't be burdened with saving. It's just quite a neat feature from the Active Record pattern - it would be nice to implement it in some way.

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  • How do I recursively delete all files or folders whose names match a pattern in Windows?

    - by zylstra
    For the file example, I would like to delete all files matching .+?[a-f0-9]{4}.html (i.e. any html file ending in a four digit hexadecimal). So paged47c.html would be deleted, but page.html would remain. For the folder example, I would like to delete all folders matching .+?[A-Z]+ (i.e. any folder containing a capital letter). So some-folderSE93_89ds/ would be deleted, but some-folder/ would remain. I don't work much with the command line, but I could probably get an example involving "del" to work for me. Alternatively, is there a simple GUI program for Windows that would do this?

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  • JavaScript local alias pattern

    - by Latest Microsoft Blogs
    Here’s a little pattern that is fairly common from JavaScript developers but that is not very well known from C# developers or people doing only occasional JavaScript development. In C#, you can use a “using” directive to create aliases of namespaces Read More......(read more)

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  • Which design pattern to use when using ORM?

    - by RPK
    I am writing a small ASP.NET Web Forms application. In my solution explorer, I added various class library projects to define layers, viz: Model Repository Presentation WebUI Someone suggested me that this layered approach is not of much sense if I am using ORM tool like PetaPoco, which itself takes care of separation of data access layer. I want to use PetaPoco micro-ORM and want to know which design pattern is suitable with ORM tools. Do I still need several class library projects to separate the concerns?

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  • The Command Pattern

    In this article I will provide a quick refresher on what the command pattern is used for, how it works, and where it fits in the web development world.

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  • Packages organisation with MVC design pattern

    - by Oltarus
    I have been programming quite a lot now and still can't decide which of these packages hierachies was the best: package1 Class1Controller Class1Model Class1View package2 Class2Controller Class2Model Class2View or controller Class1Controller Class2Contoller model Class1Model Class2Model view Class1View Class2View In other words, is it better to apply the MVC design pattern to classes or to packages? Is there any reason to choose one over the other? My question is language-agnostic, but I'm mostly a Java programmer, if it does any difference.

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