Using VB.NET 2008 I want to know what is 3 Tier Architecture for windows application? How to make a code for Inserting, Deleting, Updating in a database using 3 tier architecture.
View 5 RepliesBuilding a large application using 3 tier architecture in vb.net. Question: I am a vb.net developer. I have developed small and medium size application with 2 tier architecture. Now I am going to develop a large application. I have decided to develop that application using 3 tier architecture. So I studied about 3 tier. Now I know how what is 3 tier and how to develop a simple application. And also I studied about .Net Remoting and Web services. In my project, 7 modules are available. Each module has 3 layers. How can I manage in a Single Solution?
View 1 RepliesI have a large application that has always existed all in a single .NET project up until recently (200,000+ LOC). I'm finally getting to the point where I can fix this. I just started using the Entity Framework (4.1 using code first) and I believe this is a good time to start seperating my logic.
What I did is I separated my application into three subprojects:UI - Windows forms project Business - The POCO classes Data - Legacy data access code AND the DBContext class to connect my POCO classes to the database. I also have a Windows service project and will soon have a WCF project, but those concern me less.
The problem is that in this plan, the data layer depends on the business layer and vice versa causing a circular reference error. There is no way around this.So, my idea is to move my POCO classes into the data layer removing all business logic first (just keeping the database fields, basically). Then, I will inherit from those classes in the business layer adding back all the business rules. Then my data access layer will not rely on any other project, the business layer will rely just on the data access layer, and the interface layer will rely on both for now but eventually only on the business layer.
Does anyone see any problems with this, or a better way of doing things given my current circumstances?
I have recently built an N-Tier app using VB.Net 2008. The application is based on Beth Massi's tutorial at [URL] I am trying to incorporate a datagrridview control on a Parent form - one parent (father and mother) to many children. For example,
[Code]...
I am beginner in programming and developed an application of mine. Although, I am finished with the coding part, but I have to present my software architecture diagram. I am not a software engineer and so familiar with basics of software engineering, layering etc.I have used 1) .NET GDI Graphics in my application, 2) Text to Speech, 3) RichTextBox which retireives pictures etc. How do I proceed with the architecture diagram now?
View 1 RepliesIm trying to build my first N-Tier web application. And it seems like im doing it wrong. Ive been kinda working out of this book, but to me it doesnt seem like the right way to do this. In the book the guy builds User and Data centric objects but everywhere I see ntier everyone is always talking about BLL and DAL ive seen nothign on UC and DC objects.Right now I have Interfaces and serializable structures, user and data centric objects. The data centric object does all the validation and connecting to the db, as well as returns any violated rules, but when I once i started pulling it all together it just doesnt seem right.Ive already wrote a ____ load of code and now am kinda stuck. I dont know if i am doing this right and dont want to continue writing any code if this is all messed up.Ive been reading as much as humanly possible and im still just a little confused. I mean I understand the concepts of seperating the logic into different layers and tiers and all that but as far as my implementation of that I just feel somethings a bit off.
View 3 RepliesI have a solution and I want to divide it up into Business Tier, Data Tier, etc. I think I have to do this by creating a project that contains the data source, another with the forms, etc. Every time I try to add a new project, it literally opens a new project, seperate from the first.
View 1 Repliesi am on a project of two tier application with VB.NET + SQL server R2. except desk top applications i never done networked applications + i don't know asp.net
i require advise in few areas
(1) is the encryption required
(2) what are the security measures i must take in terms of connection security
(3) how to use the server effectively with out putting much burden through good client end design
(4) any other guide lines / pit falls
(5) should i continue with vb.net or must & should switch over to asp
(6) what should be the minimum configuration of client system,
(7) Preferable is the thin client systems , is it possible to use thin clients
I'm creating a rather large and complex application and was wondering if any of you had any recommendations for good books on application and project architecture. Multi-user - database - heavy interaction with windows api for shell extensions.Not the standard maintenance or reporting app I usually write!
View 2 RepliesI have attempted to make my first 3 tier application. In the process I have run into one problem I am yet to find an optimal solution for. Basically all my objects use an IFillable interface which forces the implementation of a sub as follows
Public Sub Fill(ByVal Datareader As Data.IDataReader) Implements IFillable.Fill
This sub then expects the Ids from the datareader will be identical to the properties of the object as such.
Me.m_StockID = Datareader.GetGuid(Datareader.GetOrdinal("StockID"))
In the end I end up with a datalayer that looks something like this.
Public Shared Function GetStockByID(ByVal ConnectionString As String, ByVal StockID As Guid) As Stock
Dim res As New Stock
Using sqlConn As New SqlConnection(ConnectionString)[code].....
Mostly this pattern seems to make sense. However my problem is, lets say I want to implement a property for Stock called StockBarcodeList.Under the above mentioned pattern any way I implement this property I will need to pass a connectionstring to it which obviously breaks my attempt at layer separation.how I might be able to solve this problem or am I going about this the completely wrong way? I am deliberately trying to avoid using the dataset in any form.
I am a fairly rookie programmer who is trying to learn the basics of n-layered architecture (DAL, BLL, UI). The application I am programming is a single tier, 3-layer application written in VB.NET (.Net 3.5). Layers as follows:
DAL
BLL
UI
COMMON - contains DTO's right now.
I am having trouble determining what to pass between my BLL and UI. My instinct tells me that I should only pass data to the UI, and not the full business object from the BLL. Consider two scenarios:
1) Pass the BO directly from BLL to UI. This exposes BO methods and allows the UI direct access to the BO, which seems bad.
2) Pass only the pertinent data from the BO to the UI. For instance, a customer has a Name and Address. This data is really what we want to show/edit in the UI, so we would only return that data to the UI instead of the full BO. The UI would then call to the BLL to update a specific BO.
I am inclined to use #2, but I don't know the best way to implement it. The way I have it programmed now, if I only return data from the BLL, all references to my BO's will be lost and the GC will claim them. Based on this, I have some questions:
1) Should I keep business objects alive between calls to the BLL? The alternative is to re-create them every time I pass data through the BLL, which seems wrong.
2) What is the best way to keep a BO alive in a single tier architecture (how to hold a reference if we dont pass it to the UI?)
3) How do n-tier applications do this? Do they keep the BO's alive in the BLL and wait for an update from the UI? Doesn't this require a lot of "book keeping" in the BLL to make sure BO's are released when they are no longer needed?
I have followed this walkthough at http:[url]...but I am having problems working out how to save changes to the Local Database Cache so that I can use the bidirectional sync. This walkthough does not provide the code to save local changes,I have added the line of code for the bidirectional sync and it works if you drag datasources direct onto the form from the XSD but this uses the component TableAdapterManager and the method UpdateALL which I cannot see how to implement in this Walkthough ?how I change the local Database Cache and update back to server in this walkthrough ?
View 6 RepliesI was wondering does anyone know where i can find some good books and or articles covering the architecture and design of OOP applications. Also I need a book that explains how to structure an application as it relates to the data tier, business logic tier, and the front end.
View 6 RepliesIn the first comment (by J.W.) to this question: Using ObjectDataSource and DataObjectTypeName, How Do You Handle Delete Methods With Just An Id Parameter?, it is said that using ObjectDataSource is a bad design. What is considered good design for well-architected ASP.NET applications?
View 1 RepliesTo write a effecient Active Directory library to ease the work of technicals who are responsible to create access models into the domain controller's Active Directory. This library must allow the following:Basic operations: Add, Modify, Delete, List entries;An entry may either be an organizational unit, group or user (no further need required as of now);I thought about having a class which would represent the domain with which we want to work with.
public class Domain {
public Domain(string root) {
Root = root;
[code].....
We have a small visual basic 6.0 application with an Access DB that we would like to migrate to modern code and architecture. I am not technical, but I am believe this would be something like a .net framework with a SQL Server DB.What I am wondering about, is there any way to covert this code to a modern language/architecture? If so, what is the easist modern language to migrate to?
View 7 Replieswhat is a disconnected architecture in dot net?Why are the dataSets a disconnected architectures in dot net?
View 15 RepliesWhen trying to determine the Architecture of an OS, I ran across IntPtr.From reading the documentation, I saw this: Quote:The IntPtr type is designed to be an integer whose size is platform-specific. That is, an instance of this type is expected to be 32-bits on 32-bit hardware and operating systems, and 64-bits on 64-bit hardware and operating systems.
Since the size of IntPtr is intended to be the size of the architecture, would it be feasible to test the size and determine the OS by that? Or is there a better way?
I was thinking there might also be a way via WMI, but I don't want to use that for compatibility reason.
Is there a way to programatically determine if the OS Architecture is 32-bit or 64 -bit?
View 5 RepliesI want to understand N-tier architecture and example of application for same.
View 5 RepliesI need to write an app that that will iterate over our database, and perform various anaylsis on each record. In order to do this (partially for the learning exercise in creating plugin support) I want to use a Plugin model.
Currently, I have a simple Interface in my main app, which plugins can Implement. My app then loads all DLL's in a folder looking for ones implementing the Interface.
As you can see in the pseudo-code below, I have to keep performing a loop through all loaded plugins calling the process methods.
Sub ProcessData()
For Each Record In MyDataSet
For Each Plugin In MyPluginCollection
[Code].....
I am working on a new domain model for an application that will have order processing for items built in (well, too keep it simple for this question anyway). I have a class "VendorItem" that represents items that can be ordered. Originally the "Order" class was going to have a list of VendorItems associated with it, but I have come across problems with it so far.
Let's say that the system has been creating orders for some time just fine. One day a user comes along and decides that a vendoritem has changed price or some other detail like packaging size. I wouldn't want the previous orders to be affected by such change. At first wash I was going to make a "OrderLine" class that is basically a copy of the "VendorItem" class, but that just feels (smells?) wrong in the OO sense. Is there a better way to refactor this so I don't have copies of classes and information in the domain model?
Explain Singleton architecture of Remoting.
View 1 RepliesI need help in understanding this architecture. The person who wrote it is long gone and I'm stuck to figure it out. We are creating an object in some code from some random workflow in the web application (unimportant for my question). The object is being instantiated from a class found in a Designer.vb file. I couldn't initially see the file until I clicked the "show all files" in Solution Explorer in Visual Studio. There are 3 files linked together.. a *.xsd file, a *.Designer.vb file and a *.xsx file. The *.Designer.vb file looks to be auto-generated.
Goal:Get dbo.note.text from the dbo.note table column and place it in the dbo.exportnote.text column. I just don't understand how it's connecting to the database and getting the data from the dbo.note.text field. I want to make the query more specific (possibly put a where clause on it). But really I just want to understand how it's communicating with the database. Most of the code uses stored procedures. So I'm confused on the architecture. What would be really cool is if you can explain how this code was autogenerated. It appears that the *.xsd file is an XML file when I "View in Browser" from the Solution Explorer.Code to instantiate object of designer class:
[code]...
I downloaded a 3 tier sample code , but that has no code for related tables, I am trying to complete this.
These are the tables and part of the sample code
[CODE...]
I usually create N Tier applications with ASP .Net applications as per the advice at ASP .Net (data tutorials). Recently ive tried to create an N Tier Windows Form database application and found the method im use to (i.e. ASP .Net) doesnt really work (unless i was doing something wrong).
View 7 RepliesI'm creating an N-Tier (or at least I think its N-Tier!) solution where I have the following:
WPF client side application (presentation layer)
WCF service hosted in a windows service (data access layer)
SQL database (data layer)
Now bearing in mind this is the first time I've tried to design anything like this, I might be going about it completely the wrong way...I've created 3 examples classes that would be my 'business objects' (im not quite sure where that fits in within the layers I listed above, because these business objects would be defined in a DLL that would be used by both the presentation layer and the data access layer). You can see them here:So then in my WCF service (data access layer) I would have methods like this that would be exposed to the WPF client:These are just examples but you get the idea. Is this the right way to do something like this?I saw one design that someone had posted somewhere that basically looked to me like it merged the Business Objects and the DAL together because in their class that represented an order, they had properties like you would expect for Order Number etc etc but then they also had methods like "GetOrders" within there too.I dunno I'm still very new to this type of design but I thought that the idea of the business objects was that they just represented business items, such as orders etc, so I thought they would just purely hold properties/fields and no methods or anything like that
I am in process of designing an architecture for an application. Following is the high level requirement.
1. The basic requirement is to convert a flat file into XML
2. The input flat file can have various formats, the delimiters, the data positions may vary.
3. The output XML format is predefined. There is a specification defined in a word format, which I think I need to define it as an XSL or XSD.
I am planning to follow some design pattern. Not decided yet. The architecture should be flexible to extend the input file formats and accommodate any changes in output specification.
how to create a stable plugin architecture. Stable because I plan on opening up plugin creation to the public but I dont want a sloppy coded plugin to take down my whole application.
So I thought of using an AppDomain per plugin and I did a little seaching. But it seems that even using a temp AppDomain to load plugins and then unloading it once all assemblies have been inspected raises complexity allot and I was planing on using an AppDomain per plugin.
I feel the gained stability (if there is any at all) may be raising the complexity so much the app will never be done..
Is there another way to both create a stable application and at the same time making it extensible?
I cases where the host calls a defined function via say IPluginInterface I guess I can pack a whole lot of try catch blocks around that call but what if a plugin insisted of a timed routine that would run continously without being invoked from the host other that a starting call to StartPluginService or something like that?
If I include a plugin like that in the default AppDomain and it blows up I sure will blow my own foot off right?
I am having a windows application. That downloads files from server and write into the local directory. It works fine. When we try the same appliication in Windows 7. IT shows an error Access to the path denied (While writing to the local directory).
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