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  • How to make a character jump, both on objects and just normal jump.

    - by haxerflaxer
    Hi, I'm kind of a beginner when it comes to java programming, and I have a project in school where I'm going to create a game much like Icy Tower. And my question is, how am I going to write to make the character stand on the ground and be able to jump up on objects? Here's my code so far: Part one package Sprites; import java.awt.Image; import java.awt.event.KeyEvent; import javax.swing.ImageIcon; public class jumper { private String jump = "oka.png"; private int dx; private int dy; private int x; private int y; private Image image; public jumper() { ImageIcon ii = new ImageIcon(this.getClass().getResource(jump)); image = ii.getImage(); x = 50; y = 100; } public void move() { x += dx; y += dy; } public int getX() { return x; } public int getY() { return y; } public Image getImage() { return image; } public void keyPressed(KeyEvent e) { int key = e.getKeyCode(); if (key == KeyEvent.VK_LEFT) { dx = -5; ImageIcon ii = new ImageIcon(this.getClass().getResource("oki.png")); image = ii.getImage(); } if (key == KeyEvent.VK_RIGHT){ dx = 5; ImageIcon ii = new ImageIcon(this.getClass().getResource("oka.png")); image = ii.getImage(); } if (key == KeyEvent.VK_SPACE) { dy = -5; } if (key == KeyEvent.VK_DOWN) { dy = 5; } } public void keyReleased(KeyEvent e) { int key = e.getKeyCode(); if (key == KeyEvent.VK_LEFT) { dx = 0; } if (key == KeyEvent.VK_RIGHT){ dx = 0; } if (key == KeyEvent.VK_SPACE) { dy = 0; } if (key == KeyEvent.VK_DOWN) { dy = 0; } } } Part two package Sprites; import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Toolkit; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.KeyAdapter; import java.awt.event.KeyEvent; import javax.swing.JPanel; import javax.swing.Timer; public class board extends JPanel implements ActionListener { private Timer klocka; private jumper jumper; public board() { addKeyListener(new TAdapter()); setFocusable(true); setBackground(Color.WHITE); setDoubleBuffered(true); jumper = new jumper(); klocka = new Timer(5, this); klocka.start(); } public void paint(Graphics g) { super.paint(g); Graphics2D g2d = (Graphics2D)g; g2d.drawImage(jumper.getImage(), jumper.getX(), jumper.getY(), this); Toolkit.getDefaultToolkit().sync(); g.dispose(); } public void actionPerformed(ActionEvent e) { jumper.move(); repaint(); } private class TAdapter extends KeyAdapter { public void keyReleased(KeyEvent e) { jumper.keyReleased(e); } public void keyPressed(KeyEvent e) { jumper.keyPressed(e); } } } Part three package Sprites; import javax.swing.JFrame; public class RType extends JFrame { public RType() { add(new board()); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setSize(800, 600); setLocationRelativeTo(null); setTitle("R - type"); setResizable(false); setVisible(true); } public static void main(String[] args) { new RType(); } } I really appreciate all the help I can get!

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  • How do you make a character jump, both on objects and just normal jump?

    - by haxerflaxer
    Hi, I'm kind of a beginner when it comes to java programming, and I have a project in school where I'm going to create a game much like Icy Tower. And my question is, how am I going to write to make the character stand on the ground and be able to jump up on objects? Here's my code so far: Part one package Sprites; import java.awt.Image; import java.awt.event.KeyEvent; import javax.swing.ImageIcon; public class jumper { private String jump = "oka.png"; private int dx; private int dy; private int x; private int y; private Image image; public jumper() { ImageIcon ii = new ImageIcon(this.getClass().getResource(jump)); image = ii.getImage(); x = 50; y = 100; } public void move() { x += dx; y += dy; } public int getX() { return x; } public int getY() { return y; } public Image getImage() { return image; } public void keyPressed(KeyEvent e) { int key = e.getKeyCode(); if (key == KeyEvent.VK_LEFT) { dx = -5; ImageIcon ii = new ImageIcon(this.getClass().getResource("oki.png")); image = ii.getImage(); } if (key == KeyEvent.VK_RIGHT){ dx = 5; ImageIcon ii = new ImageIcon(this.getClass().getResource("oka.png")); image = ii.getImage(); } if (key == KeyEvent.VK_SPACE) { dy = -5; } if (key == KeyEvent.VK_DOWN) { dy = 5; } } public void keyReleased(KeyEvent e) { int key = e.getKeyCode(); if (key == KeyEvent.VK_LEFT) { dx = 0; } if (key == KeyEvent.VK_RIGHT){ dx = 0; } if (key == KeyEvent.VK_SPACE) { dy = 0; } if (key == KeyEvent.VK_DOWN) { dy = 0; } } } Part two package Sprites; import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Toolkit; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.KeyAdapter; import java.awt.event.KeyEvent; import javax.swing.JPanel; import javax.swing.Timer; public class board extends JPanel implements ActionListener { private Timer klocka; private jumper jumper; public board() { addKeyListener(new TAdapter()); setFocusable(true); setBackground(Color.WHITE); setDoubleBuffered(true); jumper = new jumper(); klocka = new Timer(5, this); klocka.start(); } public void paint(Graphics g) { super.paint(g); Graphics2D g2d = (Graphics2D)g; g2d.drawImage(jumper.getImage(), jumper.getX(), jumper.getY(), this); Toolkit.getDefaultToolkit().sync(); g.dispose(); } public void actionPerformed(ActionEvent e) { jumper.move(); repaint(); } private class TAdapter extends KeyAdapter { public void keyReleased(KeyEvent e) { jumper.keyReleased(e); } public void keyPressed(KeyEvent e) { jumper.keyPressed(e); } } } Part three package Sprites; import javax.swing.JFrame; public class RType extends JFrame { public RType() { add(new board()); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setSize(800, 600); setLocationRelativeTo(null); setTitle("R - type"); setResizable(false); setVisible(true); } public static void main(String[] args) { new RType(); } } I really appreciate all the help I can get!

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  • Flash Mouse.hide() cmd+tab(alt+tab) bring the mouse back

    - by DickieBoy
    Having a bit of trouble with Mouse.show() and losing focus of the swf This isn't my demo: but its showing the same bug http://www.foundation-flash.com/tutorials/as3customcursors/ What i do to recreate it is: mouse over the swf, hit cmd+tab to highlight another window, result is that the mouse is not brought back and is still invisible, (to get it back go to the window bar at the top of the screen and click something). I have an area in which movement is detected and an image Things I have tried package { import flash.display.Sprite; import flash.display.MovieClip; import com.greensock.*; import flash.events.*; import flash.utils.Timer; import flash.events.TimerEvent; import flash.utils.*; import flash.ui.Mouse; public class mousey_movey extends MovieClip { public var middle_of_the_flash; //pixels per second public var speeds = [0,1,3,5,10]; public var speed; public var percentage_the_mouse_is_across_the_screen; public var mouse_over_scrollable_area:Boolean; public var image_move_interval; public function mousey_movey() { middle_of_the_flash = stage.stageWidth/2; hot_area_for_movement.addEventListener(MouseEvent.MOUSE_OVER, mouseEnter); hot_area_for_movement.addEventListener(MouseEvent.MOUSE_OUT, mouseLeave); hot_area_for_movement.addEventListener(MouseEvent.MOUSE_MOVE, mouseMove); stage.addEventListener(Event.MOUSE_LEAVE, show_mouse); stage.addEventListener(MouseEvent.MOUSE_OUT, show_mouse); stage.addEventListener(Event.DEACTIVATE,show_mouse); hot_area_for_movement.alpha=0; hot_area_for_movement.x=0; hot_area_for_movement.y=34; } public function show_mouse(e) { trace(e.type) trace('show_mouse') Mouse.show(); } public function onActivate(e) { trace('activate'); Mouse.show(); } public function onDeactivate(e) { trace('deactivate'); } public function get_speed(percantage_from_middle):int { if(percantage_from_middle > 80) { return speeds[4] } else { if(percantage_from_middle > 60) { return speeds[3] } else { if(percantage_from_middle > 40) { return speeds[2] } else { if(percantage_from_middle > 20) { return speeds[1] } else { return 0; } } } } } public function mouseLeave(e:Event):void{ Mouse.show(); clearInterval(image_move_interval); } public function mouseEnter(e:Event):void{ Mouse.hide(); image_move_interval = setInterval(moveImage,1); } public function mouseMove(e:Event):void { percentage_the_mouse_is_across_the_screen = Math.round(((middle_of_the_flash-stage.mouseX)/middle_of_the_flash)*100); speed = get_speed(Math.abs(percentage_the_mouse_is_across_the_screen)); airplane_icon.x = stage.mouseX; airplane_icon.y = stage.mouseY; } public function stageMouseMove(e:Event):void{ Mouse.show(); } public function moveImage():void { if(percentage_the_mouse_is_across_the_screen > 0) { moving_image.x+=speed; airplane_icon.scaleX = -1; } else { moving_image.x-=speed; airplane_icon.scaleX = 1; } } } } Nothing too fancy, im just scrolling an image left of right at a speed which is generated by how far you are from the middle of the stage, and making an airplane moveclip follow the mouse. The events: stage.addEventListener(Event.MOUSE_LEAVE, show_mouse); stage.addEventListener(MouseEvent.MOUSE_OUT, show_mouse); stage.addEventListener(Event.DEACTIVATE,show_mouse); All fire and work correctly when in the browser, seem a little buggy when running a test through flash, was expecting this as ive experienced it before. The deactivate call even runs when testing and cmd+tabbing but shows no mouse. Any help on the matter is appreciated Thanks, Dickie

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  • Using CreateSourceQuery in CTP4 Code First

    - by Adam Rackis
    I'm guessing this is impossible, but I'll throw it out there anyway. Is it possible to use CreateSourceQuery when programming with the EF4 CodeFirst API, in CTP4? I'd like to eagerly load properties attached to a collection of properties, like this: var sourceQuery = this.CurrentInvoice.PropertyInvoices.CreateSourceQuery(); sourceQuery.Include("Property").ToList(); But of course CreateSourceQuery is defined on EntityCollection<T>, whereas CodeFirst uses plain old ICollection (obviously). Is there some way to convert? I've gotten the below to work, but it's not quite what I'm looking for. Anyone know how to go from what's below to what's above (code below is from a class that inherits DbContext)? ObjectSet<Person> OSPeople = base.ObjectContext.CreateObjectSet<Person>(); OSPeople.Include(Pinner => Pinner.Books).ToList(); Thanks! EDIT: here's my version of the solution posted by zeeshanhirani - who's book by the way is amazing! dynamic result; if (invoice.PropertyInvoices is EntityCollection<PropertyInvoice>) result = (invoices.PropertyInvoices as EntityCollection<PropertyInvoice>).CreateSourceQuery().Yadda.Yadda.Yadda else //must be a unit test! result = invoices.PropertyInvoices; return result.ToList(); EDIT2: Ok, I just realized that you can't dispatch extension methods whilst using dynamic. So I guess we're not quite as dynamic as Ruby, but the example above is easily modifiable to comport with this restriction EDIT3: As mentioned in zeeshanhirani's blog post, this only works if (and only if) you have change-enabled proxies, which will get created if all of your properties are declared virtual. Here's another version of what the method might look like to use CreateSourceQuery with POCOs public class Person { public virtual int ID { get; set; } public virtual string FName { get; set; } public virtual string LName { get; set; } public virtual double Weight { get; set; } public virtual ICollection<Book> Books { get; set; } } public class Book { public virtual int ID { get; set; } public virtual string Title { get; set; } public virtual int Pages { get; set; } public virtual int OwnerID { get; set; } public virtual ICollection<Genre> Genres { get; set; } public virtual Person Owner { get; set; } } public class Genre { public virtual int ID { get; set; } public virtual string Name { get; set; } public virtual Genre ParentGenre { get; set; } public virtual ICollection<Book> Books { get; set; } } public class BookContext : DbContext { public void PrimeBooksCollectionToIncludeGenres(Person P) { if (P.Books is EntityCollection<Book>) (P.Books as EntityCollection<Book>).CreateSourceQuery().Include(b => b.Genres).ToList(); }

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  • pass arraylist bean from android to webservice php

    - by user1547432
    i'm newbie in android with web service i'm trying to pass arraylist from android to webservice php server here's my bean code: public class ExpressionBean { public static final String EXPRESSION_ID = "expressionID"; public static final String EXPRESSION_TEXT = "expressionText"; public static final String ANS_TEXT1 = "ansText1"; public static final String ANS_TEXT2 = "ansText2"; public static final String ASSESSEE_ANSWER = "assesseeAnswer"; private String expressionID; private String expressionText; private String ansText1; private String ansText2; private String assesseeAnswer; public String getExpressionID() { return expressionID; } public void setExpressionID(String expressionID) { this.expressionID = expressionID; } public String getExpressionText() { return expressionText; } public void setExpressionText(String expressionText) { this.expressionText = expressionText; } public String getAnsText1() { return ansText1; } public void setAnsText1(String ansText1) { this.ansText1 = ansText1; } public String getAnsText2() { return ansText2; } public void setAnsText2(String ansText2) { this.ansText2 = ansText2; } public String getAssesseeAnswer() { return assesseeAnswer; } public void setAssesseeAnswer(String assesseeAnswer) { this.assesseeAnswer = assesseeAnswer; } } and here's my doInBackround on async task : protected Boolean doInBackground(Void... params) { // TODO: attempt authentication against a network service. boolean result = false; // test = new TestBean(); // int resultTest = 0; UserFunctions userFunction = new UserFunctions(); Log.d(TAG, "UID : " + mEmail); // Log.d(TAG, "resultTest : " + resultTest); JSONObject jsonTest = userFunction.storeTest(mEmail); Log.d(TAG, "After JSON TEST "); try { if (jsonTest.getString(KEY_SUCCESS) != null) { String res = jsonTest.getString(KEY_SUCCESS); JSONObject testData = jsonTest.getJSONObject(TAG_TEST); test = new TestBean(); test.setTestid(testData.getInt(TAG_TEST_ID)); test.setUid(testData.getInt(TAG_UID)); JSONArray list = new JSONArray(); String list2; for (int position = 0; position < expressionList.size(); position++) { Gson gson = new Gson(); list.put(gson.toJson(expressionList.get(position))); } Log.d(TAG, "JSONArray list coy : " + list); UserFunctions uf = new UserFunctions(); JSONObject jsonHistoryList = new JSONObject(); jsonHistoryList = uf.storeHistoryList(list.toString()); if (Integer.parseInt(res) == 1) { result = true; finish(); } else { result = false; } } } catch (JSONException e) { e.printStackTrace(); return false; } // TODO: register the new account here. return result; } and here's storeHistoryList Method : public JSONObject storeHistoryList(String list) { // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair("tag", storeHistory_tag)); params.add(new BasicNameValuePair("list", list)); JSONObject json = jsonParser.getJSONFromUrl(URL, params); return json; } i want to pass list to web service list is an arraylist ExpressionBean i used gson for convert bean to json but when i execute, the log said "error parsing data... jsonarray cannot be converted to jsonobject what i must to do? thanks

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  • Problem in arranging contents of Class in JAVA

    - by LuckySlevin
    Hi, I have some classes and I'm trying to fill the objects of this class. Here is what i've tried. (Question is at the below) public class Team { private String clubName; private String preName; private ArrayList<String> branches; public Team(String clubName, String preName) { this.clubName = clubName; this.preName = preName; branches = new ArrayList<String>(); } public Team() { // TODO Auto-generated constructor stub } public String getClubName() { return clubName; } public String getPreName() { return preName; } public ArrayList<String> getBranches() { return branches; } public void setClubName(String clubName) { this.clubName = clubName; } public void setPreName(String preName) { this.preName = preName; } public void setBranches(ArrayList<String> branches) { this.branches = branches; } } public class Branch { private ArrayList<Player> players = new ArrayList<Player>(); String brName; public Branch() {} public void setBr(String brName){this.brName = brName;} public String getBr(){return brName;} public ArrayList<Player> getPlayers() { return players; } public void setPlayers(ArrayList<Player> players) { this.players = players; } } //TEST CLASS public class test { /** * @param args * @throws IOException */ public static void main(String[] args) throws IOException { String a,b,c; String q = "q"; int brCount = 0, tCount = 0; BufferedReader input = new BufferedReader(new InputStreamReader(System.in)); Team[] teams = new Team[30]; Branch[] myBranch = new Branch[30]; for(int z = 0 ; z <30 ;z++) { teams[z] = new Team(); myBranch[z] = new Branch(); } ArrayList<String> tmp = new ArrayList<String>(); int k = 0; int secim = Integer.parseInt(input.readLine()); while(secim != 0) { if(k!=0) secim = Integer.parseInt(input.readLine()); k++; switch(secim) { case 1 : brCount = 0; a = input.readLine(); teams[tCount].setClubName(a); b= input.readLine(); teams[tCount].setPreName(b); c = input.readLine(); while(c.equals(q) == false) { if(brCount != 0) {c = input.readLine();} if(c.equals(q)== false){ myBranch[brCount].brName = c; tmp.add(myBranch[brCount].brName); brCount++; } System.out.println(brCount); } teams[tCount].setBranches(tmp); for(int i=0;i<=tCount;i++ ){ System.out.print("a :" + teams[i].getClubName()+ " " + teams[i].getPreName()+ " "); System.out.println(teams[i].getBranches());} tCount++; break; case 2: String src = input.readLine();//LATERRRRRRRr } } } } The problem is one of my class elements. I have an arraylist as an element of a class. When i enter: AAA as preName BBB as clubName c d e as Branches Then as a second element www as preName GGG as clubName a b as branches The result is coming like: AAA BBB c,d,e,a,b GGG www c,d,e,a,b Which means ArrayList part of the class is putting it on and on. I tried to use clear() method but caused problems. Any ideas.

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  • my Search method is coming up with all nulls

    - by Epic.Distortion
    Let me give a quick explanation. I took a 5 week course through a company on Java in July. They covered basic stuff, like console app, crud operations, mysql, and n-tier architecture. Since the course ended I didn't use it much because I went back to work, and other medical reasons surfaced....blah blah. I was told by the company to make a simple program to reflect what I learned. Turns out I retained very little. I decided to make a video game starage program. It would be used to stare your video games so you wouldn't have to search your bookcase(or how ever you store your games.) It is a basic console app using the crud operations with MYSQL. I can't get my search function to actually work. I have 2 layers a Presentation layer and a Logic layer. The search method allows them to search for a game by the title. when i bring run the program and use Search it only displays the title and the rest is null. here is my Presentation layer: private static Games SearchForGame() { Logic aref = new Logic(); Games g = new Games(); Scanner scanline = new Scanner(System.in); System.out.println("Please enter the name of the game you wish to find:"); g.setTitle(scanline.nextLine()); aref.SearchGame(); System.out.println(); System.out.println("Game Id: " + g.getGameId()); System.out.println("Title: " + g.getTitle()); System.out.println("Rating: " + g.getRating()); System.out.println("Platform: "+ g.getPlatform()); System.out.println("Developer: "+ g.getDeveloper()); return g; } and here is my logic layer public Games SearchGame() { Games g = new Games(); try { Class.forName(driver).newInstance(); Connection conn = DriverManager.getConnection(url+dbName,userName,password); java.sql.PreparedStatement statement = conn.prepareStatement("SELECT GameId,Title,Rating,Platform,Developer FROM games WHERE Title=?"); statement.setString(1, g.getTitle()); ResultSet rs = statement.executeQuery(); while(rs.next()){ g.setGameId(rs.getInt("GameId")); g.setTitle(rs.getString("Title")); g.setRating(rs.getString("Rating")); g.setPlatform(rs.getString("Platform")); g.setDeveloper(rs.getString("Developer")); statement.executeUpdate(); } } catch (Exception e) { e.printStackTrace(); } return g; } here is also my last results Please enter the name of the game you wish to find: Skyrim Game Id: 0 Title: Skyrim Rating: null Platform: null Developer: null any help would be greatly appreciated and thanks in advance EDIT: here is my code for my games class public class Games { public int GameId; public String Title; public String Rating; public String Platform; public String Developer; public int getGameId() { return GameId; } public int setGameId(int gameId) { return GameId = gameId; } public String getTitle() { return Title; } public String setTitle(String title) { return Title = title; } public String getRating() { return Rating; } public void setRating(String rating) { Rating = rating; } public String getPlatform() { return Platform; } public void setPlatform(String platform) { Platform = platform; } public String getDeveloper() { return Developer; } public void setDeveloper(String developer) { Developer = developer; } }

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  • NoSQL with MongoDB, NoRM and ASP.NET MVC

    - by shiju
     In this post, I will give an introduction to how to work on NoSQL and document database with MongoDB , NoRM and ASP.Net MVC 2. NoSQL and Document Database The NoSQL movement is getting big attention in this year and people are widely talking about document databases and NoSQL along with web application scalability. According to Wikipedia, "NoSQL is a movement promoting a loosely defined class of non-relational data stores that break with a long history of relational databases. These data stores may not require fixed table schemas, usually avoid join operations and typically scale horizontally. Academics and papers typically refer to these databases as structured storage". Document databases are schema free so that you can focus on the problem domain and don't have to worry about updating the schema when your domain is evolving. This enables truly a domain driven development. One key pain point of relational database is the synchronization of database schema with your domain entities when your domain is evolving.There are lots of NoSQL implementations are available and both CouchDB and MongoDB got my attention. While evaluating both CouchDB and MongoDB, I found that CouchDB can’t perform dynamic queries and later I picked MongoDB over CouchDB. There are many .Net drivers available for MongoDB document database. MongoDB MongoDB is an open source, scalable, high-performance, schema-free, document-oriented database written in the C++ programming language. It has been developed since October 2007 by 10gen. MongoDB stores your data as binary JSON (BSON) format . MongoDB has been getting a lot of attention and you can see the some of the list of production deployments from here - http://www.mongodb.org/display/DOCS/Production+Deployments NoRM – C# driver for MongoDB NoRM is a C# driver for MongoDB with LINQ support. NoRM project is available on Github at http://github.com/atheken/NoRM. Demo with ASP.NET MVC I will show a simple demo with MongoDB, NoRM and ASP.NET MVC. To work with MongoDB and  NoRM, do the following steps Download the MongoDB databse For Windows 32 bit, download from http://downloads.mongodb.org/win32/mongodb-win32-i386-1.4.1.zip  and for Windows 64 bit, download  from http://downloads.mongodb.org/win32/mongodb-win32-x86_64-1.4.1.zip . The zip contains the mongod.exe for run the server and mongo.exe for the client Download the NorM driver for MongoDB at http://github.com/atheken/NoRM Create a directory call C:\data\db. This is the default location of MongoDB database. You can override the behavior. Run C:\Mongo\bin\mongod.exe. This will start the MongoDb server Now I am going to demonstrate how to program with MongoDb and NoRM in an ASP.NET MVC application.Let’s write a domain class public class Category {            [MongoIdentifier]public ObjectId Id { get; set; } [Required(ErrorMessage = "Name Required")][StringLength(25, ErrorMessage = "Must be less than 25 characters")]public string Name { get; set;}public string Description { get; set; }}  ObjectId is a NoRM type that represents a MongoDB ObjectId. NoRM will automatically update the Id becasue it is decorated by the MongoIdentifier attribute. The next step is to create a mongosession class. This will do the all interactions to the MongoDB. internal class MongoSession<TEntity> : IDisposable{    private readonly MongoQueryProvider provider;     public MongoSession()    {        this.provider = new MongoQueryProvider("Expense");    }     public IQueryable<TEntity> Queryable    {        get { return new MongoQuery<TEntity>(this.provider); }    }     public MongoQueryProvider Provider    {        get { return this.provider; }    }     public void Add<T>(T item) where T : class, new()    {        this.provider.DB.GetCollection<T>().Insert(item);    }     public void Dispose()    {        this.provider.Server.Dispose();     }    public void Delete<T>(T item) where T : class, new()    {        this.provider.DB.GetCollection<T>().Delete(item);    }     public void Drop<T>()    {        this.provider.DB.DropCollection(typeof(T).Name);    }     public void Save<T>(T item) where T : class,new()    {        this.provider.DB.GetCollection<T>().Save(item);                }  }    The MongoSession constrcutor will create an instance of MongoQueryProvider that supports the LINQ expression and also create a database with name "Expense". If database is exists, it will use existing database, otherwise it will create a new databse with name  "Expense". The Save method can be used for both Insert and Update operations. If the object is new one, it will create a new record and otherwise it will update the document with given ObjectId.  Let’s create ASP.NET MVC controller actions for CRUD operations for the domain class Category public class CategoryController : Controller{ //Index - Get the category listpublic ActionResult Index(){    using (var session = new MongoSession<Category>())    {        var categories = session.Queryable.AsEnumerable<Category>();        return View(categories);    }} //edit a single category[HttpGet]public ActionResult Edit(ObjectId id) {     using (var session = new MongoSession<Category>())    {        var category = session.Queryable              .Where(c => c.Id == id)              .FirstOrDefault();         return View("Save",category);    } }// GET: /Category/Create[HttpGet]public ActionResult Create(){    var category = new Category();    return View("Save", category);}//insert or update a category[HttpPost]public ActionResult Save(Category category){    if (!ModelState.IsValid)    {        return View("Save", category);    }    using (var session = new MongoSession<Category>())    {        session.Save(category);        return RedirectToAction("Index");    } }//Delete category[HttpPost]public ActionResult Delete(ObjectId Id){    using (var session = new MongoSession<Category>())    {        var category = session.Queryable              .Where(c => c.Id == Id)              .FirstOrDefault();        session.Delete(category);        var categories = session.Queryable.AsEnumerable<Category>();        return PartialView("CategoryList", categories);    } }        }  You can easily work on MongoDB with NoRM and can use with ASP.NET MVC applications. I have created a repository on CodePlex at http://mongomvc.codeplex.com and you can download the source code of the ASP.NET MVC application from here

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  • Anti-Forgery Request Recipes For ASP.NET MVC And AJAX

    - by Dixin
    Background To secure websites from cross-site request forgery (CSRF, or XSRF) attack, ASP.NET MVC provides an excellent mechanism: The server prints tokens to cookie and inside the form; When the form is submitted to server, token in cookie and token inside the form are sent in the HTTP request; Server validates the tokens. To print tokens to browser, just invoke HtmlHelper.AntiForgeryToken():<% using (Html.BeginForm()) { %> <%: this.Html.AntiForgeryToken(Constants.AntiForgeryTokenSalt)%> <%-- Other fields. --%> <input type="submit" value="Submit" /> <% } %> This invocation generates a token then writes inside the form:<form action="..." method="post"> <input name="__RequestVerificationToken" type="hidden" value="J56khgCvbE3bVcsCSZkNVuH9Cclm9SSIT/ywruFsXEgmV8CL2eW5C/gGsQUf/YuP" /> <!-- Other fields. --> <input type="submit" value="Submit" /> </form> and also writes into the cookie: __RequestVerificationToken_Lw__= J56khgCvbE3bVcsCSZkNVuH9Cclm9SSIT/ywruFsXEgmV8CL2eW5C/gGsQUf/YuP When the above form is submitted, they are both sent to server. In the server side, [ValidateAntiForgeryToken] attribute is used to specify the controllers or actions to validate them:[HttpPost] [ValidateAntiForgeryToken(Salt = Constants.AntiForgeryTokenSalt)] public ActionResult Action(/* ... */) { // ... } This is very productive for form scenarios. But recently, when resolving security vulnerabilities for Web products, some problems are encountered. Specify validation on controller (not on each action) The server side problem is, It is expected to declare [ValidateAntiForgeryToken] on controller, but actually it has be to declared on each POST actions. Because POST actions are usually much more then controllers, the work would be a little crazy. Problem Usually a controller contains actions for HTTP GET and actions for HTTP POST requests, and usually validations are expected for HTTP POST requests. So, if the [ValidateAntiForgeryToken] is declared on the controller, the HTTP GET requests become invalid:[ValidateAntiForgeryToken(Salt = Constants.AntiForgeryTokenSalt)] public class SomeController : Controller // One [ValidateAntiForgeryToken] attribute. { [HttpGet] public ActionResult Index() // Index() cannot work. { // ... } [HttpPost] public ActionResult PostAction1(/* ... */) { // ... } [HttpPost] public ActionResult PostAction2(/* ... */) { // ... } // ... } If browser sends an HTTP GET request by clicking a link: http://Site/Some/Index, validation definitely fails, because no token is provided. So the result is, [ValidateAntiForgeryToken] attribute must be distributed to each POST action:public class SomeController : Controller // Many [ValidateAntiForgeryToken] attributes. { [HttpGet] public ActionResult Index() // Works. { // ... } [HttpPost] [ValidateAntiForgeryToken(Salt = Constants.AntiForgeryTokenSalt)] public ActionResult PostAction1(/* ... */) { // ... } [HttpPost] [ValidateAntiForgeryToken(Salt = Constants.AntiForgeryTokenSalt)] public ActionResult PostAction2(/* ... */) { // ... } // ... } This is a little bit crazy, because one application can have a lot of POST actions. Solution To avoid a large number of [ValidateAntiForgeryToken] attributes (one for each POST action), the following ValidateAntiForgeryTokenWrapperAttribute wrapper class can be helpful, where HTTP verbs can be specified:[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = true)] public class ValidateAntiForgeryTokenWrapperAttribute : FilterAttribute, IAuthorizationFilter { private readonly ValidateAntiForgeryTokenAttribute _validator; private readonly AcceptVerbsAttribute _verbs; public ValidateAntiForgeryTokenWrapperAttribute(HttpVerbs verbs) : this(verbs, null) { } public ValidateAntiForgeryTokenWrapperAttribute(HttpVerbs verbs, string salt) { this._verbs = new AcceptVerbsAttribute(verbs); this._validator = new ValidateAntiForgeryTokenAttribute() { Salt = salt }; } public void OnAuthorization(AuthorizationContext filterContext) { string httpMethodOverride = filterContext.HttpContext.Request.GetHttpMethodOverride(); if (this._verbs.Verbs.Contains(httpMethodOverride, StringComparer.OrdinalIgnoreCase)) { this._validator.OnAuthorization(filterContext); } } } When this attribute is declared on controller, only HTTP requests with the specified verbs are validated:[ValidateAntiForgeryTokenWrapper(HttpVerbs.Post, Constants.AntiForgeryTokenSalt)] public class SomeController : Controller { // GET actions are not affected. // Only HTTP POST requests are validated. } Now one single attribute on controller turns on validation for all POST actions. Maybe it would be nice if HTTP verbs can be specified on the built-in [ValidateAntiForgeryToken] attribute, which is easy to implemented. Specify Non-constant salt in runtime By default, the salt should be a compile time constant, so it can be used for the [ValidateAntiForgeryToken] or [ValidateAntiForgeryTokenWrapper] attribute. Problem One Web product might be sold to many clients. If a constant salt is evaluated in compile time, after the product is built and deployed to many clients, they all have the same salt. Of course, clients do not like this. Even some clients might want to specify a custom salt in configuration. In these scenarios, salt is required to be a runtime value. Solution In the above [ValidateAntiForgeryToken] and [ValidateAntiForgeryTokenWrapper] attribute, the salt is passed through constructor. So one solution is to remove this parameter:public class ValidateAntiForgeryTokenWrapperAttribute : FilterAttribute, IAuthorizationFilter { public ValidateAntiForgeryTokenWrapperAttribute(HttpVerbs verbs) { this._verbs = new AcceptVerbsAttribute(verbs); this._validator = new ValidateAntiForgeryTokenAttribute() { Salt = AntiForgeryToken.Value }; } // Other members. } But here the injected dependency becomes a hard dependency. So the other solution is moving validation code into controller to work around the limitation of attributes:public abstract class AntiForgeryControllerBase : Controller { private readonly ValidateAntiForgeryTokenAttribute _validator; private readonly AcceptVerbsAttribute _verbs; protected AntiForgeryControllerBase(HttpVerbs verbs, string salt) { this._verbs = new AcceptVerbsAttribute(verbs); this._validator = new ValidateAntiForgeryTokenAttribute() { Salt = salt }; } protected override void OnAuthorization(AuthorizationContext filterContext) { base.OnAuthorization(filterContext); string httpMethodOverride = filterContext.HttpContext.Request.GetHttpMethodOverride(); if (this._verbs.Verbs.Contains(httpMethodOverride, StringComparer.OrdinalIgnoreCase)) { this._validator.OnAuthorization(filterContext); } } } Then make controller classes inheriting from this AntiForgeryControllerBase class. Now the salt is no long required to be a compile time constant. Submit token via AJAX For browser side, once server side turns on anti-forgery validation for HTTP POST, all AJAX POST requests will fail by default. Problem In AJAX scenarios, the HTTP POST request is not sent by form. Take jQuery as an example:$.post(url, { productName: "Tofu", categoryId: 1 // Token is not posted. }, callback); This kind of AJAX POST requests will always be invalid, because server side code cannot see the token in the posted data. Solution Basically, the tokens must be printed to browser then sent back to server. So first of all, HtmlHelper.AntiForgeryToken() need to be called somewhere. Now the browser has token in both HTML and cookie. Then jQuery must find the printed token in the HTML, and append token to the data before sending:$.post(url, { productName: "Tofu", categoryId: 1, __RequestVerificationToken: getToken() // Token is posted. }, callback); To be reusable, this can be encapsulated into a tiny jQuery plugin:/// <reference path="jquery-1.4.2.js" /> (function ($) { $.getAntiForgeryToken = function (tokenWindow, appPath) { // HtmlHelper.AntiForgeryToken() must be invoked to print the token. tokenWindow = tokenWindow && typeof tokenWindow === typeof window ? tokenWindow : window; appPath = appPath && typeof appPath === "string" ? "_" + appPath.toString() : ""; // The name attribute is either __RequestVerificationToken, // or __RequestVerificationToken_{appPath}. tokenName = "__RequestVerificationToken" + appPath; // Finds the <input type="hidden" name={tokenName} value="..." /> from the specified. // var inputElements = $("input[type='hidden'][name='__RequestVerificationToken" + appPath + "']"); var inputElements = tokenWindow.document.getElementsByTagName("input"); for (var i = 0; i < inputElements.length; i++) { var inputElement = inputElements[i]; if (inputElement.type === "hidden" && inputElement.name === tokenName) { return { name: tokenName, value: inputElement.value }; } } return null; }; $.appendAntiForgeryToken = function (data, token) { // Converts data if not already a string. if (data && typeof data !== "string") { data = $.param(data); } // Gets token from current window by default. token = token ? token : $.getAntiForgeryToken(); // $.getAntiForgeryToken(window). data = data ? data + "&" : ""; // If token exists, appends {token.name}={token.value} to data. return token ? data + encodeURIComponent(token.name) + "=" + encodeURIComponent(token.value) : data; }; // Wraps $.post(url, data, callback, type). $.postAntiForgery = function (url, data, callback, type) { return $.post(url, $.appendAntiForgeryToken(data), callback, type); }; // Wraps $.ajax(settings). $.ajaxAntiForgery = function (settings) { settings.data = $.appendAntiForgeryToken(settings.data); return $.ajax(settings); }; })(jQuery); In most of the scenarios, it is Ok to just replace $.post() invocation with $.postAntiForgery(), and replace $.ajax() with $.ajaxAntiForgery():$.postAntiForgery(url, { productName: "Tofu", categoryId: 1 }, callback); // Token is posted. There might be some scenarios of custom token, where $.appendAntiForgeryToken() is useful:data = $.appendAntiForgeryToken(data, token); // Token is already in data. No need to invoke $.postAntiForgery(). $.post(url, data, callback); And there are scenarios that the token is not in the current window. For example, an HTTP POST request can be sent by an iframe, while the token is in the parent window. Here, token's container window can be specified for $.getAntiForgeryToken():data = $.appendAntiForgeryToken(data, $.getAntiForgeryToken(window.parent)); // Token is already in data. No need to invoke $.postAntiForgery(). $.post(url, data, callback); If you have better solution, please do tell me.

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  • How I understood monads, part 1/2: sleepless and self-loathing in Seattle

    - by Bertrand Le Roy
    For some time now, I had been noticing some interest for monads, mostly in the form of unintelligible (to me) blog posts and comments saying “oh, yeah, that’s a monad” about random stuff as if it were absolutely obvious and if I didn’t know what they were talking about, I was probably an uneducated idiot, ignorant about the simplest and most fundamental concepts of functional programming. Fair enough, I am pretty much exactly that. Being the kind of guy who can spend eight years in college just to understand a few interesting concepts about the universe, I had to check it out and try to understand monads so that I too can say “oh, yeah, that’s a monad”. Man, was I hit hard in the face with the limitations of my own abstract thinking abilities. All the articles I could find about the subject seemed to be vaguely understandable at first but very quickly overloaded the very few concept slots I have available in my brain. They also seemed to be consistently using arcane notation that I was entirely unfamiliar with. It finally all clicked together one Friday afternoon during the team’s beer symposium when Louis was patient enough to break it down for me in a language I could understand (C#). I don’t know if being intoxicated helped. Feel free to read this with or without a drink in hand. So here it is in a nutshell: a monad allows you to manipulate stuff in interesting ways. Oh, OK, you might say. Yeah. Exactly. Let’s start with a trivial case: public static class Trivial { public static TResult Execute<T, TResult>( this T argument, Func<T, TResult> operation) { return operation(argument); } } This is not a monad. I removed most concepts here to start with something very simple. There is only one concept here: the idea of executing an operation on an object. This is of course trivial and it would actually be simpler to just apply that operation directly on the object. But please bear with me, this is our first baby step. Here’s how you use that thing: "some string" .Execute(s => s + " processed by trivial proto-monad.") .Execute(s => s + " And it's chainable!"); What we’re doing here is analogous to having an assembly chain in a factory: you can feed it raw material (the string here) and a number of machines that each implement a step in the manufacturing process and you can start building stuff. The Trivial class here represents the empty assembly chain, the conveyor belt if you will, but it doesn’t care what kind of raw material gets in, what gets out or what each machine is doing. It is pure process. A real monad will need a couple of additional concepts. Let’s say the conveyor belt needs the material to be processed to be contained in standardized boxes, just so that it can safely and efficiently be transported from machine to machine or so that tracking information can be attached to it. Each machine knows how to treat raw material or partly processed material, but it doesn’t know how to treat the boxes so the conveyor belt will have to extract the material from the box before feeding it into each machine, and it will have to box it back afterwards. This conveyor belt with boxes is essentially what a monad is. It has one method to box stuff, one to extract stuff from its box and one to feed stuff into a machine. So let’s reformulate the previous example but this time with the boxes, which will do nothing for the moment except containing stuff. public class Identity<T> { public Identity(T value) { Value = value; } public T Value { get; private set;} public static Identity<T> Unit(T value) { return new Identity<T>(value); } public static Identity<U> Bind<U>( Identity<T> argument, Func<T, Identity<U>> operation) { return operation(argument.Value); } } Now this is a true to the definition Monad, including the weird naming of the methods. It is the simplest monad, called the identity monad and of course it does nothing useful. Here’s how you use it: Identity<string>.Bind( Identity<string>.Unit("some string"), s => Identity<string>.Unit( s + " was processed by identity monad.")).Value That of course is seriously ugly. Note that the operation is responsible for re-boxing its result. That is a part of strict monads that I don’t quite get and I’ll take the liberty to lift that strange constraint in the next examples. To make this more readable and easier to use, let’s build a few extension methods: public static class IdentityExtensions { public static Identity<T> ToIdentity<T>(this T value) { return new Identity<T>(value); } public static Identity<U> Bind<T, U>( this Identity<T> argument, Func<T, U> operation) { return operation(argument.Value).ToIdentity(); } } With those, we can rewrite our code as follows: "some string".ToIdentity() .Bind(s => s + " was processed by monad extensions.") .Bind(s => s + " And it's chainable...") .Value; This is considerably simpler but still retains the qualities of a monad. But it is still pointless. Let’s look at a more useful example, the state monad, which is basically a monad where the boxes have a label. It’s useful to perform operations on arbitrary objects that have been enriched with an attached state object. public class Stateful<TValue, TState> { public Stateful(TValue value, TState state) { Value = value; State = state; } public TValue Value { get; private set; } public TState State { get; set; } } public static class StateExtensions { public static Stateful<TValue, TState> ToStateful<TValue, TState>( this TValue value, TState state) { return new Stateful<TValue, TState>(value, state); } public static Stateful<TResult, TState> Execute<TValue, TState, TResult>( this Stateful<TValue, TState> argument, Func<TValue, TResult> operation) { return operation(argument.Value) .ToStateful(argument.State); } } You can get a stateful version of any object by calling the ToStateful extension method, passing the state object in. You can then execute ordinary operations on the values while retaining the state: var statefulInt = 3.ToStateful("This is the state"); var processedStatefulInt = statefulInt .Execute(i => ++i) .Execute(i => i * 10) .Execute(i => i + 2); Console.WriteLine("Value: {0}; state: {1}", processedStatefulInt.Value, processedStatefulInt.State); This monad differs from the identity by enriching the boxes. There is another way to give value to the monad, which is to enrich the processing. An example of that is the writer monad, which can be typically used to log the operations that are being performed by the monad. Of course, the richest monads enrich both the boxes and the processing. That’s all for today. I hope with this you won’t have to go through the same process that I did to understand monads and that you haven’t gone into concept overload like I did. Next time, we’ll examine some examples that you already know but we will shine the monadic light, hopefully illuminating them in a whole new way. Realizing that this pattern is actually in many places but mostly unnoticed is what will enable the truly casual “oh, yes, that’s a monad” comments. Here’s the code for this article: http://weblogs.asp.net/blogs/bleroy/Samples/Monads.zip The Wikipedia article on monads: http://en.wikipedia.org/wiki/Monads_in_functional_programming This article was invaluable for me in understanding how to express the canonical monads in C# (interesting Linq stuff in there): http://blogs.msdn.com/b/wesdyer/archive/2008/01/11/the-marvels-of-monads.aspx

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  • Maintaining State in Mud Engine

    - by Johnathon Sullinger
    I am currently working on a Mud Engine and have started implementing my state engine. One of the things that has me troubled is maintaining different states at once. For instance, lets say that the user has started a tutorial, which requires specific input. If the user types "help" I want to switch in to a help state, so they can get the help they need, then return them to the original state once exiting the help. my state system uses a State Manager to manage the state per user: public class StateManager { /// <summary> /// Gets the current state. /// </summary> public IState CurrentState { get; private set; } /// <summary> /// Gets the states available for use. /// </summary> /// <value> public List<IState> States { get; private set; } /// <summary> /// Gets the commands available. /// </summary> public List<ICommand> Commands { get; private set; } /// <summary> /// Gets the mob that this manager controls the state of. /// </summary> public IMob Mob { get; private set; } public void Initialize(IMob mob, IState initialState = null) { this.Mob = mob; if (initialState != null) { this.SwitchState(initialState); } } /// <summary> /// Performs the command. /// </summary> /// <param name="message">The message.</param> public void PerformCommand(IMessage message) { if (this.CurrentState != null) { ICommand command = this.CurrentState.GetCommand(message); if (command is NoOpCommand) { // NoOperation commands indicate that the current state is not finished yet. this.CurrentState.Render(this.Mob); } else if (command != null) { command.Execute(this.Mob); } else if (command == null) { new InvalidCommand().Execute(this.Mob); } } } /// <summary> /// Switches the state. /// </summary> /// <param name="state">The state.</param> public void SwitchState(IState state) { if (this.CurrentState != null) { this.CurrentState.Cleanup(); } this.CurrentState = state; if (state != null) { this.CurrentState.Render(this.Mob); } } } Each of the different states that the user can be in, is a Type implementing IState. public interface IState { /// <summary> /// Renders the current state to the players terminal. /// </summary> /// <param name="player">The player to render to</param> void Render(IMob mob); /// <summary> /// Gets the Command that the player entered and preps it for execution. /// </summary> /// <returns></returns> ICommand GetCommand(IMessage command); /// <summary> /// Cleanups this instance during a state change. /// </summary> void Cleanup(); } Example state: public class ConnectState : IState { /// <summary> /// The connected player /// </summary> private IMob connectedPlayer; public void Render(IMob mob) { if (!(mob is IPlayer)) { throw new NullReferenceException("ConnectState can only be used with a player object implementing IPlayer"); } //Store a reference for the GetCommand() method to use. this.connectedPlayer = mob as IPlayer; var server = mob.Game as IServer; var game = mob.Game as IGame; // It is not guaranteed that mob.Game will implement IServer. We are only guaranteed that it will implement IGame. if (server == null) { throw new NullReferenceException("LoginState can only be set to a player object that is part of a server."); } //Output the game information mob.Send(new InformationalMessage(game.Name)); mob.Send(new InformationalMessage(game.Description)); mob.Send(new InformationalMessage(string.Empty)); //blank line //Output the server MOTD information mob.Send(new InformationalMessage(string.Join("\n", server.MessageOfTheDay))); mob.Send(new InformationalMessage(string.Empty)); //blank line mob.StateManager.SwitchState(new LoginState()); } /// <summary> /// Gets the command. /// </summary> /// <param name="message">The message.</param> /// <returns>Returns no operation required.</returns> public Commands.ICommand GetCommand(IMessage message) { return new NoOpCommand(); } /// <summary> /// Cleanups this instance during a state change. /// </summary> public void Cleanup() { // We have nothing to clean up. return; } } With the way that I have my FSM set up at the moment, the user can only ever have one state at a time. I read a few different posts on here about state management but nothing regarding keeping a stack history. I thought about using a Stack collection, and just pushing new states on to the stack then popping them off as the user moves out from one. It seems like it would work, but I'm not sure if it is the best approach to take. I'm looking for recommendations on this. I'm currently swapping state from within the individual states themselves as well which I'm on the fence about if it makes sense to do there or not. The user enters a command, the StateManager passes the command to the current State and lets it determine if it needs it (like passing in a password after entering a user name), if the state doesn't need any further commands, it returns null. If it does need to continue doing work, it returns a No Operation to let the state manager know that the state still requires further input from the user. If null is returned, the state manager will then go find the appropriate state for the command entered by the user. Example state requiring additional input from the user public class LoginState : IState { /// <summary> /// The connected player /// </summary> private IPlayer connectedPlayer; private enum CurrentState { FetchUserName, FetchPassword, InvalidUser, } private CurrentState currentState; /// <summary> /// Renders the current state to the players terminal. /// </summary> /// <param name="mob"></param> /// <exception cref="System.NullReferenceException"> /// ConnectState can only be used with a player object implementing IPlayer /// or /// LoginState can only be set to a player object that is part of a server. /// </exception> public void Render(IMob mob) { if (!(mob is IPlayer)) { throw new NullReferenceException("ConnectState can only be used with a player object implementing IPlayer"); } //Store a reference for the GetCommand() method to use. this.connectedPlayer = mob as IPlayer; var server = mob.Game as IServer; // Register to receive new input from the user. mob.ReceivedMessage += connectedPlayer_ReceivedMessage; if (server == null) { throw new NullReferenceException("LoginState can only be set to a player object that is part of a server."); } this.currentState = CurrentState.FetchUserName; switch (this.currentState) { case CurrentState.FetchUserName: mob.Send(new InputMessage("Please enter your user name")); break; case CurrentState.FetchPassword: mob.Send(new InputMessage("Please enter your password")); break; case CurrentState.InvalidUser: mob.Send(new InformationalMessage("Invalid username/password specified.")); this.currentState = CurrentState.FetchUserName; mob.Send(new InputMessage("Please enter your user name")); break; } } /// <summary> /// Receives the players input. /// </summary> /// <param name="sender">The sender.</param> /// <param name="e">The e.</param> void connectedPlayer_ReceivedMessage(object sender, IMessage e) { // Be good memory citizens and clean ourself up after receiving a message. // Not doing this results in duplicate events being registered and memory leaks. this.connectedPlayer.ReceivedMessage -= connectedPlayer_ReceivedMessage; ICommand command = this.GetCommand(e); } /// <summary> /// Gets the Command that the player entered and preps it for execution. /// </summary> /// <param name="command"></param> /// <returns>Returns the ICommand specified.</returns> public Commands.ICommand GetCommand(IMessage command) { if (this.currentState == CurrentState.FetchUserName) { this.connectedPlayer.Name = command.Message; this.currentState = CurrentState.FetchPassword; } else if (this.currentState == CurrentState.FetchPassword) { // find user } return new NoOpCommand(); } /// <summary> /// Cleanups this instance during a state change. /// </summary> public void Cleanup() { // If we have a player instance, we clean up the registered event. if (this.connectedPlayer != null) { this.connectedPlayer.ReceivedMessage -= this.connectedPlayer_ReceivedMessage; } } Maybe my entire FSM isn't wired up in the best way, but I would appreciate input on what would be the best to maintain a stack of state in a MUD game engine, and if my states should be allowed to receive the input from the user or not to check what command was entered before allowing the state manager to switch states. Thanks in advance.

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  • Send large JSON data to WCF Rest Service

    - by Christo Fur
    Hi I have a client web page that is sending a large json object to a proxy service on the same domain as the web page. The proxy (an ashx handler) then forwards the request to a WCF Rest Service. Using a WebClient object (standard .net object for making a http request) The JSON successfully arrives at the proxy via a jQuery POST on the client webpage. However, when the proxy forwards this to the WCF service I get a Bad Request - Error 400 This doesn't happen when the size of the json data is small The WCF service contract looks like this [WebInvoke(Method = "POST", BodyStyle = WebMessageBodyStyle.Wrapped, RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json)] [OperationContract] CarConfiguration CreateConfiguration(CarConfiguration configuration); And the DataContract like this [DataContract(Namespace = "")] public class CarConfiguration { [DataMember(Order = 1)] public int CarConfigurationId { get; set; } [DataMember(Order = 2)] public int UserId { get; set; } [DataMember(Order = 3)] public string Model { get; set; } [DataMember(Order = 4)] public string Colour { get; set; } [DataMember(Order = 5)] public string Trim { get; set; } [DataMember(Order = 6)] public string ThumbnailByteData { get; set; } [DataMember(Order = 6)] public string Wheel { get; set; } [DataMember(Order = 7)] public DateTime Date { get; set; } [DataMember(Order = 8)] public List<string> Accessories { get; set; } [DataMember(Order = 9)] public string Vehicle { get; set; } [DataMember(Order = 10)] public Decimal Price { get; set; } } When the ThumbnailByteData field is small, all is OK. When it is large I get the 400 error What are my options here? I've tried increasing the MaxBytesRecived config setting but that is not enough Any ideas?

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  • How to get friendly device name from DEV_BROADCAST_DEVICEINTERFACE and Device Instance ID

    - by snicker
    I've registered a window with RegisterDeviceNotification and can successfully recieve DEV_BROADCAST_DEVICEINTERFACE messages. However, the dbcc_name field in the returned struct is always empty. The struct I have is defined as such: [StructLayout(LayoutKind.Sequential)] public struct DEV_BROADCAST_DEVICEINTERFACE { public int dbcc_size; public int dbcc_devicetype; public int dbcc_reserved; public Guid dbcc_classguid; [MarshalAs(UnmanagedType.LPStr)] public string dbcc_name; } And I'm using Marshal.PtrToStructure on the LParam of the WM_DEVICECHANGE message. Should this be working? Or even better... Is there an alternative way to get the name of a device upon connection? EDIT (02/05/2010 20:56GMT): I found out how to get the dbcc_name field to populate by doing this: [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)] public struct DEV_BROADCAST_DEVICEINTERFACE { public int dbcc_size; public int dbcc_devicetype; public int dbcc_reserved; public Guid dbcc_classguid; [MarshalAs(UnmanagedType.ByValTStr, SizeConst=255)] public string dbcc_name; } but I still need a way to get a "Friendly" name from what is int dbcc_name. It looks like the following: \?\USB#VID_05AC&PID_1294&MI_00#0#{6bdd1fc6-810f-11d0-bec7-08002be2092f} And I really just want it to say "Apple iPhone" (which is what the device is in this case).

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  • Casting good practice

    - by phenevo
    Hi, I've got 3 classes namespace ServerPart public class Car { } namespace ServerPart public class SUV:Car { public string Name {get;set;} public string Color {get;set;) } And namespace WebSericePart public class Car { } namespace WebSericePart:Car public class SUV { public string Name {get;set;} public string Color {get;set;) } And I've translator namespace WebServicepart.Translators public static class ModelToContract { public Car[] ToCars(ServerPart.Car[] modelCars) { List<Car> contractCars=new List<Car>(); foreach(ServerPart.Car modelCar in modelCars) { contractCars.Add(ToCar(modelCar); } return contractCars.ToArray(); } public Car ToCar(ServerPart.Car modelCar) { if(modelCar is ServerPart.SUV) { return ToSUV(modelCar); } else { throw new NotImplementedException("Not supported type of Car")' } } public Car ToSUV(ServerPart.Car modelCar) { SUV suv=new SUV; // suv.Name=((ServerPart.SUV)modelCar).Name suv.Color=((ServerPart.SUV)modelCar).Color // ?? Is good practice ?? Or //ServerPart.SUV suv=(ServerPart.SUV)modelCar //suv.Name=suv.Name //suv.Color=suv.Color // is better ?? return suv; } } Do I used some else bad practices ?? Or Everything is OK :) ?

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  • Process: Unable to start service com.google.android.gms.checkin.CheckinService with Intent

    - by AndyRoid
    I'm trying to build a Google map application but keep receiving this in my LogCat. I have all the permissions and meta-data set in my manifest, but am still dumbfounded by this error. Have looked everywhere on SO for this specific error but found nothing relating to com.google.android.gms.checkin A little bit about my structural hierarchy. MainActivity extends ActionBarActivity with three tabs underneath actionbar. Each tab has it's own fragment. On the gMapFragment I create a GPSTrack object from my GPSTrack class which extends Service and implements LocationListener. The problem is that when I start the application I get this message: I have all my libraries imported properly and I even added the google-play-services.jar into my libs folder. I also installed Google Play Services APKs through CMD onto my emulator. Furthermore the LocationManager lm = = (LocationManager) mContext.getSystemService(LOCATION_SERVICE); in my GPSTrack class always returns null. Why is this and how can I fix these issues? Would appreciate an explanation along with solution too, I want to understand what's going on here. ============== Code: gMapFragment.java public class gMapFragment extends SupportMapFragment { private final String TAG = "gMapFragment"; private GoogleMap mMap; protected SupportMapFragment mapFrag; private Context mContext = getActivity(); private static View view; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { if (view != null) { ViewGroup parent = (ViewGroup) view.getParent(); if (parent != null) { parent.removeView(view); } } try { super.onCreateView(inflater, container, savedInstanceState); view = inflater.inflate(R.layout.fragment_map, container, false); setupGoogleMap(); } catch (Exception e) { /* * Map already there , just return as view */ } return view; } private void setupGoogleMap() { mapFrag = (SupportMapFragment) getFragmentManager().findFragmentById( R.id.mapView); if (mapFrag == null) { FragmentManager fragManager = getFragmentManager(); FragmentTransaction fragTransaction = fragManager .beginTransaction(); mapFrag = SupportMapFragment.newInstance(); fragTransaction.replace(R.id.mapView, mapFrag).commit(); } if (mapFrag != null) { mMap = mapFrag.getMap(); if (mMap != null) { setupMap(); mMap.setOnMapClickListener(new OnMapClickListener() { @Override public void onMapClick(LatLng point) { // TODO your click stuff on map } }); } } } @Override public void onAttach(Activity activity) { super.onAttach(activity); Log.d("Attach", "on attach"); } @Override public void onDetach() { super.onDetach(); } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); } @Override public void onResume() { super.onResume(); } @Override public void onPause() { super.onPause(); } @Override public void onDestroy() { super.onDestroy(); } private void setupMap() { GPSTrack gps = new GPSTrack(mContext); // Enable MyLocation layer of google map mMap.setMyLocationEnabled(true); Log.d(TAG, "MyLocation enabled"); // Set Map type mMap.setMapType(GoogleMap.MAP_TYPE_NORMAL); // Grab current location **ERROR HERE/Returns Null** Location location = gps.getLocation(); Log.d(TAG, "Grabbing location..."); if (location != null) { Log.d(TAG, "location != null"); // Grab Latitude and Longitude double latitude = location.getLatitude(); double longitude = location.getLongitude(); Log.d(TAG, "Getting lat, long.."); // Initialize LatLng object LatLng latLng = new LatLng(latitude, longitude); Log.d(TAG, "LatLng initialized"); // Show current location on google map mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); // Zoom in on google map mMap.animateCamera(CameraUpdateFactory.zoomTo(20)); mMap.addMarker(new MarkerOptions().position( new LatLng(latitude, longitude)).title("You are here.")); } else { gps.showSettingsAlert(); } } } GPSTrack.java public class GPSTrack extends Service implements LocationListener{ private final Context mContext; private boolean isGPSEnabled = false; //See if network is connected to internet private boolean isNetworkEnabled = false; //See if you can grab the location private boolean canGetLocation = false; protected Location location = null; protected double latitude; protected double longitude; private static final long MINIMUM_DISTANCE_CHANGE_FOR_UPDATES = 10; //10 Meters private static final long MINIMUM_TIME_CHANGE_FOR_UPDATES = 1000 * 60 * 1; //1 minute protected LocationManager locationManager; public GPSTrack(Context context) { this.mContext = context; getLocation(); } public Location getLocation() { try { //Setup locationManager for controlling location services **ERROR HERE/Return Null** locationManager = (LocationManager) mContext.getSystemService(LOCATION_SERVICE); //See if GPS is enabled isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER); //See if Network is connected to the internet or carrier service isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER); if (!isGPSEnabled && !isNetworkEnabled) { Toast.makeText(getApplicationContext(), "No Network Provider Available", Toast.LENGTH_SHORT).show(); } else { this.canGetLocation = true; if (isNetworkEnabled) { locationManager.requestLocationUpdates( LocationManager.NETWORK_PROVIDER, MINIMUM_TIME_CHANGE_FOR_UPDATES, MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this); Log.d("GPS", "GPS Enabled"); if (locationManager != null) { location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER); if (location != null) { latitude = location.getLatitude(); longitude = location.getLongitude(); } } } } } catch (Exception e) { e.printStackTrace(); } return location; } public void stopUsingGPS() { if (locationManager != null) { locationManager.removeUpdates(GPSTrack.this); } } public double getLatitude() { if (location != null) { latitude = location.getLatitude(); } return latitude; } public double getLongitude() { if (location != null) { longitude = location.getLongitude(); } return longitude; } public boolean canGetLocation() { return this.canGetLocation; } public void showSettingsAlert() { AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext); //AlertDialog title alertDialog.setTitle("GPS Settings"); //AlertDialog message alertDialog.setMessage("GPS is not enabled. Do you want to go to Settings?"); alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // TODO Auto-generated method stub Intent i = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS); mContext.startActivity(i); } }); alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // TODO Auto-generated method stub dialog.cancel(); } }); alertDialog.show(); } @Override public void onLocationChanged(Location location) { // TODO Auto-generated method stub } @Override public void onStatusChanged(String provider, int status, Bundle extras) { // TODO Auto-generated method stub } @Override public void onProviderEnabled(String provider) { // TODO Auto-generated method stub } @Override public void onProviderDisabled(String provider) { // TODO Auto-generated method stub } @Override public IBinder onBind(Intent intent) { // TODO Auto-generated method stub return null; } } logcat 06-08 22:35:03.441: E/AndroidRuntime(1370): FATAL EXCEPTION: main 06-08 22:35:03.441: E/AndroidRuntime(1370): Process: com.google.android.gms, PID: 1370 06-08 22:35:03.441: E/AndroidRuntime(1370): java.lang.RuntimeException: Unable to start service com.google.android.gms.checkin.CheckinService@b1094e48 with Intent { cmp=com.google.android.gms/.checkin.CheckinService }: java.lang.SecurityException: attempting to read gservices without permission: Neither user 10053 nor current process has com.google.android.providers.gsf.permission.READ_GSERVICES. 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2719) 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.app.ActivityThread.access$2100(ActivityThread.java:135) 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1293) 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.os.Handler.dispatchMessage(Handler.java:102) 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.os.Looper.loop(Looper.java:136) 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.app.ActivityThread.main(ActivityThread.java:5017) 06-08 22:35:03.441: E/AndroidRuntime(1370): at java.lang.reflect.Method.invokeNative(Native Method) 06-08 22:35:03.441: E/AndroidRuntime(1370): at java.lang.reflect.Method.invoke(Method.java:515) 06-08 22:35:03.441: E/AndroidRuntime(1370): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779) 06-08 22:35:03.441: E/AndroidRuntime(1370): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595) 06-08 22:35:03.441: E/AndroidRuntime(1370): at dalvik.system.NativeStart.main(Native Method) 06-08 22:35:03.441: E/AndroidRuntime(1370): Caused by: java.lang.SecurityException: attempting to read gservices without permission: Neither user 10053 nor current process has com.google.android.providers.gsf.permission.READ_GSERVICES. 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.app.ContextImpl.enforce(ContextImpl.java:1685) 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.app.ContextImpl.enforceCallingOrSelfPermission(ContextImpl.java:1714) 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.content.ContextWrapper.enforceCallingOrSelfPermission(ContextWrapper.java:572) 06-08 22:35:03.441: E/AndroidRuntime(1370): at imq.c(SourceFile:107) 06-08 22:35:03.441: E/AndroidRuntime(1370): at imq.a(SourceFile:121) 06-08 22:35:03.441: E/AndroidRuntime(1370): at imq.a(SourceFile:227) 06-08 22:35:03.441: E/AndroidRuntime(1370): at bwq.c(SourceFile:166) 06-08 22:35:03.441: E/AndroidRuntime(1370): at com.google.android.gms.checkin.CheckinService.a(SourceFile:237) 06-08 22:35:03.441: E/AndroidRuntime(1370): at com.google.android.gms.checkin.CheckinService.onStartCommand(SourceFile:211) 06-08 22:35:03.441: E/AndroidRuntime(1370): at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2702) AndroidManifest <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.app" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="14" android:targetSdkVersion="19" /> <uses-permission android:name="com.curio.permission.MAPS_RECEIVE" /> <uses-permission android:name="android.permission.CAMERA" /> <uses-permission android:name="android.permission.INTERNET" /> <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /> <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" /> <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" /> <uses-feature android:name="android.hardware.camera" android:required="true" /> <uses-feature android:glEsVersion="0x00020000" android:required="true" /> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.app.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <meta-data android:name="com.google.android.gms.version" android:value="@integer/google_play_services_version" /> <meta-data android:name="com.google.android.maps.v2.API_KEY" android:value="AI........................" /> </application>

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  • Getting Nested Object Property Value Using Reflection

    - by Kumar
    I have the following two classes: public class Address { public string AddressLine1 { get; set; } public string AddressLine2 { get; set; } public string City { get; set; } public string State { get; set; } public string Zip { get; set; } } public class Employee { public string FirstName { get; set; } public string MiddleName { get; set; } public string LastName { get; set; } public Address EmployeeAddress { get; set; } } I have an instance of the employee class as follows: var emp1Address = new Address(); emp1Address.AddressLine1 = "Microsoft Corporation"; emp1Address.AddressLine2 = "One Microsoft Way"; emp1Address.City = "Redmond"; emp1Address.State = "WA"; emp1Address.Zip = "98052-6399"; var emp1 = new Employee(); emp1.FirstName = "Bill"; emp1.LastName = "Gates"; emp1.EmployeeAddress = emp1Address; I have a method which gets the property value based on the property name as follows: public object GetPropertyValue(object obj ,string propertyName) { var objType = obj.GetType(); var prop = objType.GetProperty(propertyName); return prop.GetValue(obj, null); } The above method works fine for calls like GetPropertyValue(emp1, "FirstName") but if I try GetPropertyValue(emp1, "Address.AddressLine1") it throws an exception because objType.GetProperty(propertyName); is not able to locate the nested object property value. Is there a way to fix this?

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  • ASP.NET MVC 2: Mechanics behind an Order / Order Line in a edit form

    - by Dr. Zim
    In this question I am looking for links/code to handle an IList<OrderLine> in an MVC 2 edit form. Specifically I am interested in sending a complete order to the client, then posting the edited order back to an object (to persist) using: Html.EditorFor(m = m.orderlines[i]) (where orderlines is an enumerable object) Editing an Order that has multiple order lines (two tables, Order and OrderLine, one to many) is apparently difficult. Is there any links/examples/patterns out there to advise how to create this form that edits an entity and related entities in a single form (in C# MVC 2)? The IList is really throwing me for a loop. Should I have it there (while still having one form to edit one order)? How could you use the server side factory to create a blank OrderLine in the form while not posting the entire form back to the server? I am hoping we don't treat the individual order lines with individual save buttons, deletes, etc. (for example, they may open an order, delete all the lines, then click cancel, which shouldn't have altered the order itself in either the repository nor the database. Example classes: public class ViewModel { public Order order {get;set;} // Only one order } public class Order { public int ID {get;set;} // Order Identity public string name {get;set;} public IList<OrderLine> orderlines {get;set;} // Order has multiple lines } public class OrderLine { public int orderID {get;set;} // references Order ID above public int orderLineID {get;set;} // Order Line identity (need?) public Product refProduct {get;set;} // Product value object public int quantity {get;set;} // How many we want public double price {get;set;} // Current sale price }

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  • C# - Help with LINQ

    - by cmaduro
    I need to check if a certain property exists within a class. Please refer to the LINQ query in question. For the life of me I cannot make the compiler happy. class Program { static void Main(string[] args) { ModuleManager m = new ModuleManager(); IModule module = m.FindModuleForView(typeof(HomeView)); Console.WriteLine(module.GetType().ToString()); Console.ReadLine(); } } public class ModuleManager { [ImportMany] public IEnumerable<Lazy<IModule>> Modules { get; set; } [ImportMany] public IEnumerable<Lazy<View>> Views { get; set; } public ModuleManager() { //An aggregate catalog that combines multiple catalogs var catalog = new AggregateCatalog(); //Adds all the parts found in the same assembly as the Program class catalog.Catalogs.Add(new AssemblyCatalog(typeof(Program).Assembly)); //Create the CompositionContainer with the parts in the catalog _container = new CompositionContainer(catalog); //Fill the imports of this object try { this._container.ComposeParts(this); } catch (CompositionException compositionException) { Console.WriteLine(compositionException.ToString()); } } public IModule FindModuleForView(Type view) { //THIS IS THE PROBLEM var module = from m in Modules where ( from p in m.Value.GetType().GetProperties() where p.GetType().Equals(view) select p ) select m; } public CompositionContainer _container { get; set; } } public interface IModule { } [Export] public class HomeModule : IModule { public HomeModule() { } [Export] public HomeView MyHomeView { get { return new HomeView(); } set { } } } public class HomeView : View { } public class View { }

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  • InvalidCastException in DataGridView

    - by Max Yaffe
    (Using VS 2010 Beta 2 - .Net 4.0 B2 Rel) I have a class, MyTable, derived from BindingList where S is a struct. S is made up of several other structs, for example: public class MyTable<S>:BindingList<S> where S: struct { ... } public struct MyStruct { public MyReal r1; public MyReal r2; public MyReal R1 {get{...} set{...}} public MyReal R2 {get{...} set{...}} ... } public struct MyReal { private Double d; private void InitFromString(string) {this.d = ...;} public MyReal(Double d) { this.d = d;} public MyReal(string val) { this.d = default(Double); InitFromString(val);} public override string ToString() { return this.real.ToString();} public static explicit operator MyReal(string s) { return new MyReal(s);} public static implicit operator String(MyReal r) { return r.ToString();} ... } OK, I use the MyTable as a binding source for a DataGridView. I can load the data grid easily using InitFromString on individual fields in MyStruct. The problem comes when I try to edit a value in a cell of the DataGridView. Going to the first row, first column, I change the value of the existing number. It gives an exception blizzard, the first line of which says: System.FormatException: Invalid cast from 'System.String' to 'MyReal' I've looked at the casting discussions and reference books but don't see any obvious problems. Any ideas?

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  • Example with Visitor Pattern

    - by devoured elysium
    public class Song { public string Genre { get; protected set; } public string Name { get; protected set; } public string Band { get; protected set; } public Song(string name, string band, string genre) { Name = name; Genre = genre; Band = band; } } public interface IMusicVisistor { void Visit(List<Song> items); } public class MusicLibrary { List<Song> _songs = new List<Song> { ...songs ... }; public void Accept(IMusicVisitor visitor) { visitor.Visit(_songs); } } and now here's one Visitor I made: public class RockMusicVisitor : IMusicVisitor { public List<Song> Songs { get; protected set; } public void Visit(List<Song> items) { Songs = items.Where(x => x.Genre == "Rock").ToList(); } } Why is this any better than just putting a public property Songs and then letting any kind of class do with it anything that it wants to? This example comes from this post.

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  • Cannot return view model after POST

    - by Interfector
    HI, I am trying to return a model after a POST but I receive the following error: Exception Details: System.InvalidOperationException: Operation is not valid due to the current state of the object. Line 29: public UsersModel getUser(Int32 id) { Line 30: return ( Line 31: from users in db.NUsers Line 32: join userSettings in db.NUsersSettings The code in the controller looks like this: [AcceptVerbs( HttpVerbs.Post )] public ActionResult Edit( NUsers user ) { //Other code that doesn't affect the error :) UsersModel userDetails = this.usersObj.getUser( user.UserID ); return View( userDetails ); } The getUser method looks like this: public UsersModel getUser(Int32 id) { return ( from users in db.NUsers join userSettings in db.NUsersSettings on users.UserID equals userSettings.UserID where users.UserID == id select new UsersModel { UserId = Convert.ToInt32( users.UserID ), Email = Convert.ToString( users.Email ), FirstName = Convert.ToString( users.FirstName ), LastName = Convert.ToString( users.LastName ), Language = Convert.ToString( userSettings.Language ), Phone = Convert.ToString( users.Phone ) } ).First(); } and finally the UsersModel if you think it is relevant: public class UsersModel { public int UserId; public string Email; public string FirstName; public string LastName; public string Language; public string Phone; public List<NLanguages> Languages; public UsersModel() { Models.Languages languagesObj = new Models.Languages(); Languages = languagesObj.getLanguages(); } } Any thoughts on what might be causing the error and what can I do to fix it? Thx

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  • why assign null value or another default value firstly?

    - by Phsika
    i try to generate some codes. i face to face delegates. Everythings is ok.(Look below) But appearing a warning: you shold assing value why? but second code below is ok. namespace Delegates { class Program { static void Main(string[] args) { HesapMak hesapla = new HesapMak(); hesapla.Calculator = new HesapMak.Hesap(hesapla.Sum); double sonuc = hesapla.Calculator(34, 2); Console.WriteLine("Toplama Sonucu:{0}",sonuc.ToString()); Console.ReadKey(); } } class HesapMak { public double Sum(double s1, double s2) { return s1 + s2; } public double Cikarma(double s1, double s2) { return s1 - s2; } public double Multiply(double s1, double s2) { return s1 * s2; } public double Divide(double s1, double s2) { return s1 / s2; } public delegate double Hesap(double s1, double s2); public Hesap Calculator; ----&#60; they want me assingn value } } namespace Delegates { class Program { static void Main(string[] args) { HesapMak hesapla = new HesapMak(); hesapla.Calculator = new HesapMak.Hesap(hesapla.Sum); double sonuc = hesapla.Calculator(34, 2); Console.WriteLine("Toplama Sonucu:{0}",sonuc.ToString()); Console.ReadKey(); } } class HesapMak { public double Sum(double s1, double s2) { return s1 + s2; } public double Cikarma(double s1, double s2) { return s1 - s2; } public double Multiply(double s1, double s2) { return s1 * s2; } public double Divide(double s1, double s2) { return s1 / s2; } public delegate double Hesap(double s1, double s2); public Hesap Calculator=null; } }

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  • Model relationships in ASP.NET MVC

    - by Fabiano
    Hi I recently started evaluating ASP.NET MVC. While it is really easy and quick to create Controllers and Views for Models with only primitive properties (like shown in the starter videos from the official page) I didn't find any good way to work with references to complex types. Let's say, I have these Models: public class Customer { public int Id { get; set; } public string Name { get; set; } public Address Address { get; set; } public IList<Order> Orders { get; set; } } public class Address { public int Id { get; set; } public string ..... ..... } public class Order { public int Id { get; set; } public Customer Customer { get; set; } public string OrderName { get; set; } ..... } Note that I don't have foreign keys in the models (like it's typical for LINQ to SQL, which is also used in the sample video) but an object reference. How can I handle such references in asp.net mvc? Does someone has some good tips or links to tutorials about this problem? maybe including autobinding with complex types.

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  • What is the best practice for using lock within inherited classes

    - by JDMX
    I want to know if one class is inheriting from another, is it better to have the classes share a lock object that is defined at the base class or to have a lock object defined at each inheritance level. A very simple example of a lock object on each level of the class public class Foo { private object thisLock = new object(); private int ivalue; public int Value { get { lock( thisLock ) { return ivalue; } } set { lock( thisLock ) { ivalue= value; } } } } public class Foo2: Foo { private object thisLock2 = new object(); public int DoubleValue { get { lock( thisLock2 ) { return base.Value * 2; } } set { lock( thisLock2 ) { base.Value = value / 2; } } } } public class Foo6: Foo2 { private object thisLock6 = new object(); public int TripleDoubleValue { get { lock( thisLock6 ) { return base.DoubleValue * 3; } } set { lock( thisLock6 ) { base.DoubleValue = value / 3; } } } } A very simple example of a shared lock object public class Foo { protected object thisLock = new object(); private int ivalue; public int Value { get { lock( thisLock ) { return ivalue; } } set { lock( thisLock ) { ivalue= value; } } } } public class Foo2: Foo { public int DoubleValue { get { lock( thisLock ) { return base.Value * 2; } } set { lock( thisLock ) { base.Value = value / 2; } } } } public class Foo6: Foo2 { public int TripleDoubleValue { get { lock( thisLock ) { return base.DoubleValue * 3; } } set { lock( thisLock ) { base.DoubleValue = value / 3; } } } } Which example is the preferred way to manage locking within an inherited class?

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  • Factory Method Pattern clarification

    - by nettguy
    My understanding of Factory Method Pattern is (Correct me if i am wrong) Factory Method Pattern "Factory Method allow the client to delegates the product creation (Instance Creation) to the subclass". There are two situation in which we can go for creating Factory Method pattern. (i) When the client is restricted to the product (Instance) creation. (ii) There are multiple products available.But a decision to be made which product instance need to be returned. If you want to create Abstract Method pattern You need to have abstract product Concrete Product Factory Method to return the appropriate product. Example : public enum ORMChoice { L2SQL, EFM, LS, Sonic } //Abstract Product public interface IProduct { void ProductTaken(); } //Concrete Product public class LinqtoSql : IProduct { public void ProductTaken() { Console.WriteLine("OR Mapping Taken:LinqtoSql"); } } //concrete product public class Subsonic : IProduct { public void ProductTaken() { Console.WriteLine("OR Mapping Taken:Subsonic"); } } //concrete product public class EntityFramework : IProduct { public void ProductTaken() { Console.WriteLine("OR Mapping Taken:EntityFramework"); } } //concrete product public class LightSpeed : IProduct { public void ProductTaken() { Console.WriteLine("OR Mapping Taken :LightSpeed"); } } public class Creator { //Factory Method public IProduct ReturnORTool(ORMChoice choice) { switch (choice) { case ORMChoice.EFM:return new EntityFramework(); break; case ORMChoice.L2SQL:return new LinqtoSql(); break; case ORMChoice.LS:return new LightSpeed(); break; case ORMChoice.Sonic:return new Subsonic(); break; default: return null; } } } **Client** Button_Click() { Creator c = new Creator(); IProduct p = c.ReturnORTool(ORMChoice.L2SQL); p.ProductTaken(); } Is my understanding of Factory Method is correct?

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