Search Results

Search found 14326 results on 574 pages for 'design by contract'.

Page 155/574 | < Previous Page | 151 152 153 154 155 156 157 158 159 160 161 162  | Next Page >

  • Enterprise Platform in Python, Design Advice

    - by Jason Miesionczek
    I am starting the design of a somewhat large enterprise platform in Python, and was wondering if you guys can give me some advice as to how to organize the various components and which packages would help achieve the goals of scalability, maintainability, and reliability. The system is basically a service that collects data from various outside sources, with each outside source having its own separate application. These applications would poll a central database and get any requests that have been submitted to perform on the external source. There will be a main website and REST/SOAP API that should also have access to the central data service. My initial thought was to use Django for the web site, web service and data access layer (using its built-in ORM), and then the outside source applications can use the web service(s) to get the information they need to process the request and save the results. Using this method would allow me to have multiple instances of the service applications running on the same or different machines to balance out the load. Are there more elegant means of accomplishing this? i've heard of messaging systems such as MQ, would something like that be beneficial in this scenario? My other thought was to use a completely separate data service not based on Django, and use some kind of remoting or remote objects (in they exist in Python) to interact with the data model. The downside here would be with the website which would become much slower if it had to push all of its data requests through a second layer. I would love to hear what other developers have come up with to achieve these goals in the most flexible way possible.

    Read the article

  • MVC design for archived data view

    - by Hemant Tank
    Implementation of a standard archive process in ASP.Net MVC. Backend SQL Server 2005 We've an existing web app built in MVC. We've an Entity "Claim" and it has some child entities like ClaimDetails, Files, etc... A pretty standard setup in DB. Each entity has its own table and are linked via FK. Now, we need to have an "Archive" feature in web app which will allow admin to archive a Claim and its child entities. An archived Claim shud become readonly when visited again. Here're some points on which I need your valued opinion - To keep it simple and scalable (for a few million records) for now we plan to simply add a bit field "Archived" to the Claim table in db. And change the behavior accordingly in the web app. We've a 'Manage claim' page which renders a bunch of diff views for Claim and its child entities. Now, for a readonly view we can either use the same views or have a separate set of views. What do you suggest? At controller level, we can identify archived claim and select which view to render. At model level, though it'd be great to be able to use the same model used for Manage Claim - but it might not get us the "text" of some lookup fields. For example, Claim.BrandId is rendered as a dropdown in Manage claim (requires only BrandId) but for readonly view we need 'BrandText'. Any existing ref or architecture level example would be great. Here's my prev SO post but its more about db level changes: Design a process to archive data (SQL Server 2005) Thank you.

    Read the article

  • OO Design: use Properties or Overloaded methods?

    - by Robert Frank
    Question about OO design. Suppose I have a base object vehicle. And two descendants: truck and automobile. Further, suppose the base object has a base method: FixFlatTire(); abstract; When the truck and automobile override the base object's, they require different information from the caller. Am I better off overloading FixFlatTire like this in the two descendant objects: Procedure Truck.FixFlatTire( OfficePhoneNumber: String; NumberOfAxles: Integer): Override; Overload; Procedure Automobile.FixFlatTire( WifesPhoneNumber: String; AAAMembershipID: String): Override; Overload; Or introducing new properties in each of the descendants and then setting them before calling FixFlatTire, like this: Truck.OfficePhoneNumber := '555-555-1212'; Truck.NumberOfAxles := 18; Truck.FixFlatTire(); Automobile.WifesPhoneNumber := '555-555-2323'; Automobile.AAAMembershipID := 'ABC'; Automobile.FixFlatTire();

    Read the article

  • Winforms App Not Displaying Graphical Elements in Design Mode

    - by Sev
    I wrote a bunch of code in the .cs file in c# for a winforms application. The application runs fine, and everything is in it's place. Something like this: using.. namespace Temp { public class Temp : Form { Button b1; TextBox t1; Temp() { b1.Text = "Some Text"; b1.Size = new Size(50,20); ... } void function1() { // stuff } static void Main() { Application.Run(new Temp()); } } } How can I modify my code (or fix it somehow) so that the design view displays the elements in their correct positions and view so that I can visually edit them instead of having to trial/error everything. Edit for Clarification My application runs fine. The problem is, that I didn't use designer to create the application and so in the designer view, the app is empty. But not empty when I run it, since everything is positioned programmatically in the .cs file. My question is, how can I fix this, so that the designer shows the objects correctly. There is no quick fix other than to redesign everything?

    Read the article

  • Visual C# Winforms App Not Displaying Graphical Elements in Design Mode

    - by Sev
    I wrote a bunch of code in the .cs file in c# for a winforms application. The application runs fine, and everything is in it's place. Something like this: using.. namespace Temp { public class Temp : Form { Button b1; TextBox t1; Temp() { b1.Text = "Some Text"; b1.Size = new Size(50,20); ... } void function1() { // stuff } static void Main() { Application.Run(new Temp()); } } } How can I modify my code (or fix it somehow) so that the design view displays the elements in their correct positions and view so that I can visually edit them instead of having to trial/error everything. Edit for Clarification My application runs fine. The problem is, that I didn't use designer to create the application and so in the designer view, the app is empty. But not empty when I run it, since everything is positioned programmatically in the .cs file. My question is, how can I fix this, so that the designer shows the objects correctly. There is no quick fix other than to redesign everything?

    Read the article

  • Design patterns for Caching Images in a MVC?

    - by Onema
    Hi, I'm designing an image cache system that will be used in an MVC CMS. The main purpose of the image cacher is to modify images: scale, crop, etc and cache them in the client site. I have created an image cache Model and Mapper that interact with the Database, to keep track of the images and know what kind of actions have been applied to them (scale, crop, etc). In addition to the Model and Mapper I have created a ImageCacher Class that is used by the API to manage the Model and image creation based on arguments passed by the client site, this class creates the images and generates the links to the images for the View. A coworker argued that I need to include the functionality of this last Class inside the Model, as the bulk of the logic should go in the model. I respectfully disagree with him since I feel the model's responsibility is to deal with the information about the images cached at the database level, and the responsibility of the ImageCacher Class is to create the url/image that we will be caching (keeping the single responsibility principle). In addition to this I believe that a model should not have Presentation-related features, like creating or showing images. Does anyone have any insight on this? is there a particular design pattern that would make this division of tasks clear and and the image cacher reusable? Should I add all the logic in the Model? Thank you.

    Read the article

  • Grid related UI design question

    - by younevertell
    Grid related UI design question I want some 16-grid (4 rows and 4 columns) user interface, and fill the grid with some round shapes. I also want to use the MouseOver, mouse left button down, and Mouse Left Button Up events to set the state of grids as selected or not selected. My questions: 1. How fill the grid with some round shapes? by SetColumn and SetRow? 2. How to make the grids respond to the mouse please? Thanks <Grid.ColumnDefinitions> <ColumnDefinition /> <ColumnDefinition /> <ColumnDefinition /> <ColumnDefinition /> </Grid.ColumnDefinitions> <Grid.RowDefinitions> <RowDefinition /> <RowDefinition /> <RowDefinition /> <RowDefinition /> </Grid.RowDefinitions>

    Read the article

  • MS Access Premiere Products Exercise

    - by rynwtts
    I am working with Microsoft Access, Premiere Products Exercises for a college course. I can't seem to get past a specific question. We are working with DBDL and E-R Diagrams. The question is here. Indicate the changes you need to make to the design of the Premiere Products database to support the following situation. A customer is not necessarily represented by a single sales rep but can be represented by several sales reps. when a customer places an order, the sales rep who gets the commission on the order must be one of the collection of sales reps who represents the customer. In the database already each customer is represented by a sales rep. Which yields a one to one relationship. I need to enable a customer to have several sales reps, and make it so that only those sales rep will be eligible for commission upon each order.

    Read the article

  • uWSGI and Nginx python file handling

    - by user133507
    I've been trying to figure out how to propertly utilize uWSGI with Nginx and have hit a bit of a design roadblock. I'm trying to figure out how my python files should be accessed via uWSGI. I've been able to find 3 different ways to do so: Create a uWSGI process for each python file and then create locations in nginx that pass to each uWSGI process. Create one instance of uWSGI and create a master python file that handles all the different requests. Create one instance of uWSGI and setup dynamic applications I'm coming from LightTPD where I simply setup rewrites to point at the different python files. I feel like 3 is the closest to that but uWSGI says that it is not the recommended way of going about it.

    Read the article

  • Where to begin with IPv6 [closed]

    - by Willem de Vries
    I am fairly familiar with setting-up IPv4 networks for bigger server configurations, only now I wanted to start familiarizing myself with doing the same for IPv6. I have been Googling for the second night in a row for things like: IPv6 network design, IPv6 for dummies, etc. So far most things you find go on about why IPv6 and the amazing amount of numbers that we have now. Yet I am looking for practical stuff, for example: what would be a good way to assign IP-number, as I understand it DHCP shouldn't be the default course of action. How do other assignment methods work with DNS configuration? what would be a good or standard way of dividing the network in to sub-nets? (database, application, web servers spread over multiple domains/applications and some what intertwined) In short I would like to find good resources with practical information books, webpages, etc.

    Read the article

  • How to apply Data Oriented Design with Object Oriented Programming?

    - by Pombal
    I've read lots of articles about Data Oriented Design (DOD) and I understand it but I can't design an Object Oriented Programming (OOP) system with DOD in mind, I think my OOP education is blocking me. How should I think to mix the two? The objective is to have a nice OOP interface while using DOD behind the scenes. I saw this too but didn't help much: http://stackoverflow.com/questions/3872354/how-to-apply-dop-and-keep-a-nice-user-interface

    Read the article

  • How to display values from another website to an new html page?

    - by user3098728
    How to display the value in a new html file from different website? This an example field of values that need to display into new html file and I want to display the said values in the input box (Contract ID) of this page JSFiddle. I have 2 JS code that would display that values, but unfortunately its not working and I dont know how to display that value in html input box. Please help me. Thank you I want to display the said value in this input box: Here the JS file to read the values: function scanLapVerification() { try { var page_title = "Title"; var el = getElement(document, "class", "view-operator-verification-title", ""); if (!el || el.length == 0) return; if (el[0].innerText != page_title) return; var page_title = ''; var el = getElement(document, "class", "workflowActivityDetailPanel", ""); if (el && el.length > 0) { var eltr = getElement(el[0], "tag", "tr", ""); if (eltr && eltr.length > 0) { //Read Contract ID var contractId = { CI: { id: null } }; var con_id = null; for (var i = 0; i < eltr.length; i++) { tr_text = eltr[i].innerText; if (tr_text.substr(0, "Contract ID".length) == "Contract ID") con_id = "CI"; if (con_id && tr_text.substr(0, "Contract ID".length) == "Contract ID") { contractId[con_id].id = tr_text.substr("Contract ID".length + 1, tr_text.length - "Contract ID".length - 1); } } var contract_id = contractId.CI.id; return { content: "cid_check", con_id: con_id }; } return { status: "KO" }; } catch (e) { alert("Exception: scanLapVerification\n" + e.Description); return { status: "KO", message: e }; } }; And here's the 2nd JS that display to a new html page: function scanLapVerification() { chrome.tabs.sendRequest(tabLapVerification, { method: "scanLapVerification" }, function (response) { msgbox("receiveResponse: scanLapVerification " + jsonToString(response, "JSON")); //maintaining state in the background if (response.data.content == "cid_check") { //Popup window features var popupWindow = null; var name; var width = 550; var height = 200; var left = parseInt((screen.availWidth / 2) - (width / 2)); var top = parseInt((screen.availHeight / 2) - (height / 2)); var windowFeatures = "width=" + width + ",height=" + height + ",left=" + left + ",top=" + top + "screenX=" + left + ",screenY=" + top; //Input new address with popup window if (confirm("Does the client has new address?") == true) { popupWindow = window.open('/htmlname.htm', "title", windowFeatures + encodeURIComponent(response.data.contract_id)); popupWindow.focus(); } else { name = ""; } }); }

    Read the article

  • Change Tweetmeme button colour under wordpress

    - by Andrew Bolster
    I've had a poke around in the TweetMeme plugin code and IANA JS Guru, but I cant find any sensible way to make specific styling changes; you can add div-specific CSS characteristics, but I'm talking about changing the resting colour and the hover colour of the button. I've googled around and noone seems to have asked it on here so I thought I should. PS I would not be surprised by this question being migrated to SO, but since this is more of a design/use question rather than a programming question, I thought it was worth trying here first.

    Read the article

  • Grid Style. Is It The Next Big Thing In Web Design?

    Inspired by typographic magazine layout grids more and more web designers are starting to embrace grid-based design siting cleaner and more easily digestible web pages as a benefit. The concept of ... [Author: Michiel Van Kets - Web Design and Development - June 17, 2010]

    Read the article

  • Building a News-feed that comprises posts "created by user's connections" && "on the topics user is following"

    - by aklin81
    I am working on a project of Questions & Answers website that allows a user to follow questions on certain topics from his network. A user's news-feed wall comprises of only those questions that have been posted by his connections and tagged on the topics that he is following(his expertise topics). I am confused what database's datamodel would be most fitting for such an application. The project needs to consider the future provisions for scalability and high performance issues. I have been looking at Cassandra and MySQL solutions as of now. After my study of Cassandra I realized that Simple news-feed design that shows all the posts from network would be easy to design using Cassandra by executing fast writes to all followers of a user about the post from user. But for my kind of application where there is an additional filter of 'followed topics', (ie, the user receives posts "created by his network" && "on topics user is following"), I could not convince myself with a good schema design in Cassandra. I hope if I missed something because of my short understanding of cassandra, perhaps, can you please help me out with your suggestions of how this news-feed could be implemented in Cassandra ? Looking for a great project with Cassandra ! Edit: There are going to be maximum 5 tags allowed for tagging the question (ie, max 5 topics can be tagged on a question).

    Read the article

  • Two objects with dependencies for each other. Is that bad?

    - by Kasper Grubbe
    Hi SO. I am learning a lot about design patterns these days. And I want to ask you about a design question that I can't find an answer to. Currently I am building a little Chat-server using sockets, with multiple Clients. Currently I have three classes. Person-class which holds information like nick, age and a Room-object. Room-class which holds information like room-name, topic and a list of Persons currently in that room. Hotel-class which have a list of Persons and a list of Rooms on the server. I have made a diagram to illustrate it (Sorry for the big size!): http://i.imgur.com/Kpq6V.png I have a list of players on the server in the Hotel-class because it would be nice to keep track of how many there are online right now (Without having to iterate through all of the rooms). The persons live in the Hotel-class because I would like to be able to search for a specific Person without searching the rooms. Is this bad design? Is there another way of achieve it? Thanks.

    Read the article

  • Game architecture: modeling different steps/types of UI

    - by Sander
    I have not done any large game development projects, only messed around with little toy projects. However, I never found an intuitive answer to a specific design question. Namely, how are different types/states of UI modeled in games? E.g. how is a menu represented? How is it different from a "game world" state (let's use an FPS as an example). How is an overlaid menu on top of a "game world" modeled? Let's imagine the main loop of a game. Where do the game states come into play? It it a simple case-by-case approach? if (menu.IsEnabled) menu.Process(elapsedTime); if (world.IsEnabled) world.Process(elapsedTime); if (menu.IsVisible) menu.Draw(); if (world.IsVisible) world.Draw(); Or are menu and world represented somewhere in a different logic layer and not represented at this level? (E.g. a menu is just another high-level entity like e.g. player input or enemy manager, equal to all others) foreach (var entity in game.HighLevelEntities) entity.Process(elapsedTime); foreach (var entity in game.HighLevelEntities) entity.Draw(elapsedTime); Are there well-known design patterns for this? Come to think of it, I don't know any game-specific design patterns - I assume there are others, as well? Please tell me about them.

    Read the article

  • Where can a self-teacher learn general good programming habits and conventions?

    - by lucid
    A few mistakes and general childishness in early adulthood have left me in a situation where I work a menial job, with no possibility (in the near future) of attending school. I aspire to one day work in the programming field (gaming specifically), after proving myself on the indie end of things. I've gotten very confident in C++, java, and python, and I find I'm able to solve any problem I want either from previous experience, or from scouring the web for help. The solutions work, and with each attempt they become more readable, maintainable, and extensible. But this is because I'm learning from mistakes and bad programming and design habits I feel I might have avoided with actual schooling. General tips like: "if it's hard to read or getting long, or you're writing it twice, it should be in one or more functions." or "design all your classes before you start coding, so you don't have to rewrite classes later when you discover an unforeseen dependency" Is there a good book or website for learning general good programming practices and design habits? Also, naming and format conventions. I realize sometimes development houses have their own conventions, but things like "Classes in python usually have the first letter of each word capitalized". I'd like to be able to show some source code to a potential employer, and be prepared when for what's expected on a team. Is there some central database of naming and formatting conventions somewhere? Also, feel free to give any thoughts on whether or not the self-teach, garner some indie sales, use them as your resume' route is realistic

    Read the article

  • C++ Matrix class hierachy

    - by bpw1621
    Should a matrix software library have a root class (e.g., MatrixBase) from which more specialized (or more constrained) matrix classes (e.g., SparseMatrix, UpperTriangluarMatrix, etc.) derive? If so, should the derived classes be derived publicly/protectively/privately? If not, should they be composed with a implementation class encapsulating common functionality and be otherwise unrelated? Something else? I was having a conversation about this with a software developer colleague (I am not per se) who mentioned that it is a common programming design mistake to derive a more restricted class from a more general one (e.g., he used the example of how it was not a good idea to derive a Circle class from an Ellipse class as similar to the matrix design issue) even when it is true that a SparseMatrix "IS A" MatrixBase. The interface presented by both the base and derived classes should be the same for basic operations; for specialized operations, a derived class would have additional functionality that might not be possible to implement for an arbitrary MatrixBase object. For example, we can compute the cholesky decomposition only for a PositiveDefiniteMatrix class object; however, multiplication by a scalar should work the same way for both the base and derived classes. Also, even if the underlying data storage implementation differs the operator()(int,int) should work as expected for any type of matrix class. I have started looking at a few open-source matrix libraries and it appears like this is kind of a mixed bag (or maybe I'm looking at a mixed bag of libraries). I am planning on helping out with a refactoring of a math library where this has been a point of contention and I'd like to have opinions (that is unless there really is an objective right answer to this question) as to what design philosophy would be best and what are the pros and cons to any reasonable approach.

    Read the article

  • What's the best way to store Logon User information for Web Application?

    - by Morgan Cheng
    I was once in a project of web application developed on ASP.NET. For each logon user, there is an object (let's call it UserSessionObject here) created and stored in RAM. For each HTTP request of given user, matching UserSessoinObject instance is used to visit user state information and connection to database. So, this UserSessionObject is pretty important. This design brings several problems found later: 1) Since this UserSessionObject is cached in ASP.NET memory space, we have to config load balancer to be sticky connection. That is, HTTP request in single session would always be sent to one web server behind. This limit scalability and maintainability. 2) This UserSessionObject is accessed in every HTTP request. To keep the consistency, there is a exclusive lock for the UserSessionObject. Only one HTTP request can be processed at any given time because it must to obtain the lock first. The performance and response time is affected. Now, I'm wondering whether there is better design to handle such logon user case. It seems Sharing-Nothing-Architecture helps. That means long user info is retrieved from database each time. I'm afraid that would hurt performance. Is there any design pattern for long user web app? Thanks.

    Read the article

  • How to understand existing projects

    - by John
    Hi. I am a trainee developer and have been writing .NET applications for about a year now. Most of the work I have done has involved building new applications (mainly web apps) from scratch and I have been given more or less full control over the software design. This has been a great experience however, as a trainee developer my confidence about whether the approaches I have taken are the best is minimal. Ideally I would love to collaborate with more experienced developers (I find this the best was I learn) however in the company I work for developers tend to work in isolation (a great shame for me). Recently I decided that a good way to learn more about how experienced developers approach their design might be to explore some open source projects. I found myself a little overwhelmed by the projects I looked at. With my level of experience it was hard to understand the body of code I faced. My question is slight fuzzy one. How do developers approach the task of understanding a new medium to large scale project. I found myself pouring over lots of code and struggling to see the wood for the trees. At any one time I felt that I could understand a small portion of the system but not see how its all fits together. Do others get this same feeling? If so what approaches do you take to understanding the project? Do you have any other advice about how to learn design best practices? Any advice will be very much appreciated. Thank you.

    Read the article

  • Implementing search functionality with multiple optional parameters against database table.

    - by quarkX
    Hello, I would like to check if there is a preferred design pattern for implementing search functionality with multiple optional parameters against database table where the access to the database should be only via stored procedures. The targeted platform is .Net with SQL 2005, 2008 backend, but I think this is pretty generic problem. For example, we have customer table and we want to provide search functionality to the UI for different parameters, like customer Type, customer State, customer Zip, etc., and all of them are optional and can be selected in any combinations. In other words, the user can search by customerType only or by customerType, customerZIp or any other possible combinations. There are several available design approaches, but all of them have some disadvantages and I would like to ask if there is a preferred design among them or if there is another approach. Generate sql where clause sql statement dynamically in the business tier, based on the search request from the UI, and pass it to a stored procedure as parameter. Something like @Where = ‘where CustomerZip = 111111’ Inside the stored procedure generate dynamic sql statement and execute it with sp_executesql. Disadvantage: dynamic sql, sql injection Implement a stored procedure with multiple input parameters, representing the search fields from the UI, and use the following construction for selecting the records only for the requested fields in the where statement. WHERE (CustomerType = @CustomerType OR @CustomerType is null ) AND (CustomerZip = @CustomerZip OR @CustomerZip is null ) AND ………………………………………… Disadvantage: possible performance issue for the sql. 3.Implement separate stored procedure for each search parameter combinations. Disadvantage: The number of stored procedures will increase rapidly with the increase of the search parameters, repeated code.

    Read the article

  • Eclipc java,writting a program [closed]

    - by ghassar
    I have an important exercise for that i found in the internet please i need help in using eclipc java thanks i have to design, implement, test and document a Java program (a set of classes) for one of the following problem specifications: Problem 1 – Jubilee Estate Agency Property Management System A local Estate Agent would like a prototype system to keep track of properties that are offered for sale. The Estate Agent sells domestic and commercial properties. You will need to define classes that represent the Estate Agency System. You should design your system and the classes that you will need before starting coding. Your system must have a graphical user interface and be designed and developed using the object-oriented principles of the MVC architecture design pattern i.e. the user interface class must be separate from the other classes. The initial basic requirements for the system are as follows: • Include a list of domestic properties for sale that include details of: address, description, selling price, and number of rooms • Include a list of commercial properties for sale that include details of: address, description, selling price, and area in square metres • Enable the properties that are for sale to be viewed on the screen • Allow the customer to select one or more properties to be placed on a ‘viewing list’ so that the properties can be visited in person • Display on the screen the viewing list that shows the details of the properties chosen • Provide a basic search facility to find properties that are for sale in a particular price band and display the results • Enable a property to be marked as sold

    Read the article

  • design of orm tool

    - by ifree
    Hello , I want to design a orm tool for my daily work, but I'm always worry about the mapping of foreign key. Here's part of my code: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data; namespace OrmTool { [AttributeUsage(AttributeTargets.Property)] public class ColumnAttribute:Attribute { public string Name { get; set; } public SqlDbType DataType { get; set; } public bool IsPk { get; set; } } [AttributeUsage(AttributeTargets.Class,AllowMultiple=false,Inherited=false)] public class TableAttribute:Attribute { public string TableName { get; set; } public string Description { get; set; } } [AttributeUsage(AttributeTargets.Property)] public class ReferencesAttribute : ColumnAttribut { public Type Host { get; set; } public string HostPkName{get;set;} } } I want to use Attribute to get the metadata of Entity ,then mapping them,but i think it's really hard to get it done; public class DbUtility { private static readonly string CONNSTR = ConfigurationManager.ConnectionStrings["connstr"].ConnectionString; private static readonly Type TableType = typeof(TableAttribute); private static readonly Type ColumnType = typeof(ColumnAttribute); private static readonly Type ReferenceType = typeof(ReferencesAttribute); private static IList<TEntity> EntityListGenerator<TEntity>(string tableName,PropertyInfo[] props,params SqlParameter[] paras) { return null; } private static IList<TEntity> ResultList() { return null; } private static SqlCommand PrepareCommand(string sql,SqlConnection conn,params SqlParameter[] paras) { SqlCommand cmd = new SqlCommand(); cmd.CommandText = sql; cmd.Connection = conn; if (paras != null) cmd.Parameters.AddRange(paras); conn.Open(); return cmd; } } I don't know how to do the next step, if every Entity has it's own foreign key,how do I get the return result ? If the Entity like this: [Table(Name="ArtBook")] public class ArtBook{ [column(Name="id",IsPk=true,DataType=SqlDbType.Int)] public int Id{get;set;} [References(Name="ISBNId",DataType=SqlDataType.Int,Host=typeof(ISBN),HostPkName="Id")] public ISBN BookISBN{get;set;} public .....more properties. } public class ISBN{ public int Id{get;set;} public bool IsNative{get;set;} } If I read all ArtBooks from database and when I get a ReferencesAttribute how do I set the value of BookISBN?

    Read the article

  • Sockets server design advice

    - by Rob
    We are writing a socket server in c# and need some advice on the design. Background: Clients (from mobile devices) connect to our server app and we leave their socket open so we can send data back down to them whenever we need to. The amount of data varies but we generally send/receive data from each client every few seconds, so it's quite intensive. The amount of simultaneous connections can range from 50-500 (and more in the future). We have already written a server app using async sockets and it works, however we've come across some stumbling blocks and we need to make sure that what we're doing is correct. We have a collection which holds our client states (we have no socket/connection pool at the moment, should we?). Each time a client connects we create a socket and then wait for them to send us some data and in receiveCallBack we add their clientstate object to our connections dictionary (once we have verified who they are). When a client object then signs off we shutdown their socket and then close it as well as remove them from our collection of clients dictionary. Presumably everything happens in the right order, everything works as expected. However, almost everyday it stops accepting connections, or so we think, either that or it connects but doesn't actually do anything past that and we can't work out why it's just stopping. There are few things that we'r'e unsure about 1) Should we be creating some kind of connection pool as opposed to just a dictionary of client sockets 2) What happens to the sockets that connect but then don't get added to our dictionary, they just linger around in memory doing nothing, should we create ANOTHER dictionary that holds the sockets as soon as they are created? 3) What's the best way of finding if clients are no longer connected? We've read some many methods but we're not sure of the best one to use, send data or read data, if so how? 4) If we loop through the connections dictonary to check for disposed clients, should we be locking the dictionary, if so how does this affect other clients objects trying to use it at the same time, will it throw an error or just wait? 5) We often get disposedSocketException within ReceiveCallBack method at random times, does this mean we are safe to remove that socket from the collection? We can't seem to find any production type examples which show any of this working. Any advice would be greatly received

    Read the article

< Previous Page | 151 152 153 154 155 156 157 158 159 160 161 162  | Next Page >