I am new to this .NET what is the difference between N-Tier and 3- Tier Architecture. If they are same. How to pass the values from presentation layer to business logic layer.
For Example
I have 10 controls in presentation layer. I passing values to these controls. How the architecture works.
I am building a web site following the tutorials on asp.net. I am using dataset as data access lay, and writing classes to access the dataset. But the example is just basic ideas, how do I retrieve individual table column value in the business layer?For example, if I have a table called Product, I only want to find out what is the product name by product id. I did this in my ProductBLL:
public ProductBLL
{
public int GetProductName(string productId)
{
ProductDataSet.ProductDataTable prodData = Adapter.GetProductById(productId);
[code]...
Is there a better way, or am I doing this correctly? Can anybody give me a reference to a more complicated business logic model?
I've even got my JQuery Ajax submission going on now but I've encountered another problem. I *think* it's something to do with the structure I'm using but like I say, I'm fairly newo this.I have my AJAX form submission which builds my "PersonViewModel" (model for the presentation layer) in JSON and sends it to "@Url.Action("RegisterSubmit")" in my Person Controller. Now, I seperate my business layer from my View/presentation layer so in "RegisterSubmit"I'm verifying the model is valid then instantiating a new instance of my business model "Person", adding the values from "PersonViewModel" and then calling my "Save" function.
View 7 Replieshere i have in 3-tier architecture , how to pass the data between DAL and BAL. i am using grid view to edit the data,when ever i click on the edit button all the corresponding fields should come to textboxes. i tried for delete ,it works fine bt not working to EDIT.
View 7 RepliesI have to pass the session value to a business logic layer, I can pass it to the function from presentation layer but how can I access it directly in my business logic layer ? Also is it a good approach to pass it directly to business logic layer like
GetMyRecords(Count,Session["userID"].toString()); ?
how the data pass from one layer to another layer in mvc design pattern...
View 2 RepliesI'am using enterprise library data access block in my asp.net application. I want to implement transaction from the Business logic layer, across multiple stored procs. Entlib opens a new connection for database access. Does using Transaction Scope in the following way lead to distributed transaction?
using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required))
{
// calling necessary DAL methods
scope.Complete();
}
Is there better methods to implement transaction from BLL?
I am trying to estimate how long it will take to migrate a Classic ASP application to .NET and came across hundreds of COM functions written in VB 6.
A majority of these functions only do parameter validation and actually calls the SQL server. Is this something that should be replace with an ORM? (Linq, nHibernate, Entity Framework)... or should there be more to this picture?
I've a static page method in web form application and I want to call method on private class level variable from it as shown below. I'm using jQuery to call the page method.
private readonly ICatalogBLL _catalogBLL = new CatalogBLL();
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
_catalogBLL.GetSomething();
}
}
[WebMethod]
public static UpdateSomething(int i)
{
//Want to do as below. But can't call it from a static method.
_catalogBLL.UpdateSomething();
}
UPDATE If I call it as said by John Saunders, won't it use the same instance for requests from different users as it is within a static method?
I know there are a few posts on this issue already, however I haven't found the answers I was really looking for.
My situation is like this: I have a DLL project containing my business logic. Then I have a web application that refers to this DLL, and calls a function from it. And I have a global.asax which handles errors on Application_Error
Sample:
// MyWebsite.aspx.cs
using MyBusinessLogic;
protected void Page_Load(object sender, EventArgs e)
{
MyBusinessLogicClass.DoSomething();
}
// global.asax.cs
protected void Application_Error(object sender, EventArgs e)
[Code].....
We're building a large web app that has numerous layers. In order to communicate to the business layer we're using a service layer that the web layer calls when data is needed. Unfortunately, it seems that if exceptions are thrown in the business layer, it seems that the services on the web side are wrapping the exceptions and re-throwing them. We're looking for a clear way to encapsulate the error and log it, without WCF wrapping a new exception around the original.
View 2 RepliesI creating 3 tier arch wpp in VS 2010. I added the BusinessAccessLayer refernce in Presentation Layer. and I created DataAccessLayer[DAL] and ORM [DBModel.DBML]. when i try to create the instance for the Table in presenation layer[default.aspx], The Table name is not shown.After adding the DataAccessLayer refernce in the presentation layer, the table name[MM_User] instance are shown.Is it the right method [Adding the DAL refernce in Presenation Layer]? If not, whats the solution for for accessing the instance of the tables[MM_User].Is it related to the Creating the DataContextWrapper class in DAL?
View 5 RepliesI am implementing 3-tier architecture. I just wanted to know the role of business layer in 3-tier architecture.
I am developing application in using entity framework. So I have entity object which is accessiable in PL,BL & DL. My question is whether input assignment to entity object should be in PL OR BL.(Consider there is save method)
I am creating an ASP.NET MVC application and want to display an icon in the view based on a value of a property in the model. I guess I want to have the logic deciding which image to show in the business layer (which is in a separate class library project) but the actual images files in the web application's "Content" folder. Should I set the url of the image in the business layer? I don't want the business layer to know that is serves a web application, it can be a Windows Form or WPF application as well. If I set the url with System.Web.HttpContext.Current.Server.MapPath it feels like I am getting an unwanted dependency on System.Web, right? What are the options here?
View 1 RepliesI'm trying to reevaluate our n-layer architecture and would love to get some based on your experiences. Here is our typical .NET n-layer (sometimes n-tier) design.
Project.UI
Project.Services
Project.Business
Project.Model
Project.DataAccess
DataAccess typically consists of Entity Framework 4 and Repository classes. I attempt to follow the Aggregate Root concept in order to avoid having a repository for table, easier said than done in my experience. I tend to have ~70% match between Repositories and Tables.
Model usually consists of my Entity Framework 4 entities, I've been using Self-Tracking EF entities with success.
Business is what I struggle with the most. I typically have a Manager class for every Repository. This class will contain methods like .Add() which will perform business validation before forwarding down to repository.Add().
Services, typically I will only implement this if in fact I am looking to create a web service based solution. This layer will be tasked with marshaling requests/responses between DTOs and entities. And most importantly provide the more coarse grained interface. For example a TradingService.SubmitTrade(), which is really a facade for a business transaction which might include AccountManager.ValidateCash(), OrderManager.SubmitOrder(), etc.
My business layer is very entity centric, really it's just the glue between the entities and the repository, with validation in between. I've seen many designs where the Service Layer is what holds a reference to the repositories (in essence skipping the "business layer"). In essence it serves the same purpose as my Business layer, it does the validation, however its' responsibility (and naming) is a higher level, more coarse grained business transaction. Using the example above the TradingService.submitTrade() will not delegate to any business manager classes, it would itself query the necessary repositories, perform all the validation etc.
I like my design in a sense that I can reuse a business layer method in multiple service calls, however I hate the fact that for every repository I have a matching business layer manager, creating tons of extra work. Maybe the solution is a different type of grouping at the Business Layer level? For example combine individual Manager classes like PhoneManager and EmailManager (note I have Phone entities and Email entities) into a logical Manager class such as ContactsManager (note I don't have a "Contact" entity type). With methods such as ContactManager.GetPhones() and ContactManager.GetEmail(), etc.
I am working on implementing a web application in ASP.Net by following the MVC design pattern (Not ASP.Net MVC). As part of the design, we have entity objects that has only properties as per the corresponding table structure and the idea is using these entity objects in the view layer and the same entity objects are passed to Persistence Layer for saving the data to the database. Business Objects in the business layer are responsible for interacting with the database.
As view creates the entity objects and passes to next layer, what would be the best practice to pass the entity objects to the business layer? Should the business objects accept data objects as parameters and interact with the persistence layer? Is there any other best practice to pass the required objects from the view layer to the next layer? As business objects also need to access the properties of the entity objects passed from the view layer, do we need any "translation" from entity objects to business objects?
the best practices to pass entity objects from view layer to the next layer and also how the entity objects created by the persistence layer can be used by business objects?
I am going to develop new application in asp.net .But I want to create business/data access layer in such a way that I can reuse it in any other interface (Smart Phones,php etc).how can I achieve this ?I need to create project architect according to that.
View 2 Repliesis there any impact of using static methods in Business Access layer in 3 tier applciation,
View 4 RepliesWe are using a tierd design with a Data Access Layer and classes for everything we need. This serves as an advantage because we do not have to write querys over and we can separate the Presentation layer from the Data Access Layer and Business Rules.I have always in the past populated GridViews, DataLists, repeaters,etc with SqlDataSources. This is what I have become accustomed to and I feel like it is simple. For querys such as Select * from Members, I feel like using a DataSource is simpler than having to go in the code and calling methods to populate and DataBind these presentation controls.
I am working with a gentleman who has introduced me to the world of Data Access Layers and we are breaking everything down into simeple, but effective queries to populate controls and do what we need to accomplish with this application. He is not very approving of using any type of DataSource. We are disagreeing on the time and place to use these class methods to call the database.So my question is, which is more widely used in the programming world? Do most people use DataSources to populate presentation controls regardless of the Data Access Layer they are working with? Which type of queries are best suited for a DAL - simple, populating queries or complicated joins and upserts?
I was wondering if setting a default value for a SelectList is considered to be presentation logic or business logic? For example, if a requirement is that an Employee cannot be saved without a Location, but 99% of the time the location that would be selected is a particular item -- say Atlanta. Because of this, the location SelectList should be defaulted to Atlanta when ever a entry screen for a new employee is displayed. Should I be defaulting the location in the model or in the view-model? One thing I realized is that the unit tests become awkward because in both cases, I'd be forced to test against a location that will always be present in production but I cannot create a unit test with my own test dataunless "Atlanta" was in the set of locations being used in the test.
View 4 RepliesWhat is the best way to unit test the presentation layer of a web forms application? I have been told that there are frameworks available like Watin. Are there better tools around?
View 1 RepliesWe are designing a system that has functionality that is essentially the same at the presentation layer and the exposed API layer. My question is what technique / strategy to use so we can get the most reuse out of our code with performance in mind? Here's a simplified example: A user can add a Customer via a web form. This will fire the Customer.Create() method. An API consumer / user can add a Customer via a SOAP / HTTP-POST to a web service which will call the Customer.Create() method.
Imagine these layers:
PRESENTATION
|
|
WEB SERVICE API (Customer.Create() is available here
|
|
FACADE Business Object Interface - Customer.Create() signature is here
|
|
BUSINESS Business object - Customer.Create method() is fleshed out here
|
|
DATA ACCESS - Writes data
The presentation layer SOAP calls the Create() web method, which calls the facade's Create() method which calls the business object's Create() method which wires via the data access layer.
Questions:
Is there a concern about performance in using the API's web services in our presentation layer, or are there alternatives to connect the presentation layer directly to the facade? If so, what technology to use (WCF, Remoting, Web Services, etc)?
Actually what i am doing in my Data Access Layer dragging store procedure to TestDbml to display records and creating data context instance in BAL to retrieve records and my method in BAL is like this
public IEnumerable display()
{
using (TestDataContext db = new TestDataContext())
{
var display = obj.USP_Actor_View_Speciality(p_UserName, 1);
return display as IEnumerable;
}
Now the problem is that how can i iterate or fetch over the records and display accordingly in my Presentation Layer so that i could return all the field parameteres Like ield1=val.field1,field2=val.field2.
I'm wondering how can I use LINQ in here?
Code:
public Northwind.ProductsDataTable GetProducts()
{
[Can I use Linq here?]
return Adapter.GetProducts();
}
I followed the way of using Business Layer through this tutorial and I'm wondering how I can use LINQ there:
What is the best way (for a .Net 4 project) to implement authorization in the business layer. Simply I want to check whether a certain identity can access a certain action/resource.
I've tried to look this up in Patterns & Practices, but haven't found anything useful yet.
And what about PrincipalPermission of ASP.Net 2.0? Is this still relevant? What about maintenance?
I want to use an elegant solution, preferably (re)using asp.net role management.