I have a potential project where I would be working on developing the "Data Access Layer" of a reporting application using ADO.Net and LINQToSQL.
I have not specifically worked on a Data Access Layer project (middle tier), so I was wondering if anyone here could provide a sample / example / resource, where I can get an idea of what the project entails.
I am working on a project in which I have made changes to LINQ to SQL code in data access layer project.Initially the code was using Single() extension method, I have changed it to SingleOrDefault() was earlier method was throwing exception if no records found in db.
After making changes I ran the project but during debugging VS 2008 was showing that file is changed and do you want to reload the file box. When selected the file, the debugger was still executing the commented code (Single() method).I tried cleaning the entire solution and rebuilding it but it did not help. All the projects (Presentation, BL, DAL) are under single solution.
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?
here 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 RepliesIam facing the problem with creating the Data Access layer using Dataset.xsd file and How to access the data from the file.
View 2 RepliesIn old style i used to return datasets to BOL (From DAL) and then to Website. but in 3.5 is there any new way to construct DAL. i heard about returning List<> is better than DataSet. I Got to build new DAL for my new project. if i should go for List <> aprroach can i use Linq to Sql technique or shall i go for execute dataset (using applicatio block libraries) and then fill data in List<> prior to return it back to BOL.
View 1 RepliesI want to get the .cs class file that we use when we work with the data base. and then I can just include it in all the files.
it should contain all the information like rundbquery, runstoredproc,runstoredprocwithparams....etc.
I am developing a web application in Visualt Studio 2008. I have a data access layer that is automatically generated using Visual Studio. After publising my site to IIS and tested it for several hours, two exceptions occured:
[Code]....
The connection string is stored in the data access layer in Properties.Settings and has not changed.Does anyone have a clue why these exceptions occur and how i can avoid them?
I have been researching for a while and have actually created a prototype ASP.NET web service as a DAL for a few ASP.NET 2.0 web sites. Just would like to ask for some insight/advice from more experienced developers out there who had successfully rolled out DAL as a web service. What are the drawbacks/risks to deploying DAL as a web service? What is the best way to secure or authenticate consumption of this web service? WCF is out of the question, I'll be coding in VS 2005.
View 4 Replies I've VS2008 and enterprise library 4.1 installed .I want to display few records in the categories table of my NorthWind in my presentation layer through data access layer with enterprise library. I've added references of the following dlls in my data access layer project( which is of type class library)
Microsoft.Practices.EnterpriseLibrary.Common
Microsoft.Practices.EnterpriseLibrary.Data
Microsoft.Practices.ObjectBuilder2
how to access data from the database using datareader , entity beans and rendering data on to presentation layer.
I'm now reading this article:[URL]But I don't understnad why this is better than just writing code, methods that connects to DB and get from stored procedore what I need.
Why is it better to use so much DataSets for all the tables and more.
I'm trying to retrive images from SQL (2005) using ASP.NET 2008
At present I have a business object layer and a data access layer to get some data from the database. This works fine but now, i would like to also retrive an image along with the data.
part of my business object layer is shown below, how can i incorporate the image into this.
I have a DLL file which will take care of displaying the image in the web page once i have retrived it.
[Code]....
I am developing a web application, which has Data Access Layer and this layer has only one class, in which all methods are static methods like static Insert, static Update, static Search. It has no properties. I am using these methods in my Bussiness Logic class for my users who are visiting my website.Now my question is : 1. Is it right to use static methods in this scenario ?2. What will happen if 10 users call Insert method at the same time ?
View 3 RepliesI have created a table adapter in DAL. I have created a gridview in the page and want to fill the gridview with a table data by calling a method. My table has 11 columns but i want to display only 2 columns of the table. My getSong() method has a query as Select title, category from Muisc. But it diaplyas all columns with no data except title and category and the autoincrement primary key column with negative values. The pic is given below. How can i solve it?
View 2 RepliesI am creating my application in asp.net 3.5. I have to make my Data Access layer, in which I am doing the traditional method of fetching/updating the data. Which is SqlConnection than SQLCommand, than SQLadapter. Will there be any other way I can create my DAL layer easily.
Specification.
My website is small. Approx 7-10 pages. Database has around 80 tables.
What I know:
Linq to SQL - I don't want to use it because I am not fully aware about the LINQ statement and I need to develop the application really fast. [3 days :-( ]. Also, there are 100% chances that the table structure will be altered in future. Enterprise Library: It will take too much time for me to integrate to my application.
I can use similar code below to select a row in my database when I enter a value (username) in text box and it successfully retrieves.however, I'd also like to delete row from database based on the username i enter in text box. My code runs but no row is deleted...my code is:
SQL:
private AdminTableAdapter adminGetUsers;
I have written the following functions(1 & 2) in a class file(say abc.vb) to execute a sql statement in code behind.
[Code]....
I am learning on how to create data access layer code for a web site. I want to ensure I am actually connecting to the datasource, so, I am wanting to use a try/catch block within my data access layer class methods. What I am not sure how to handle is a case where the connectionstate is not open. The method should ideally return a datatable. If an error is thrown would I just return an empty datatable? That is my first thought. My other thought is to return an object and pass a datatable if the connection succeeds or the exception if the connection fails.
View 10 RepliesI am working on a small website for project management.There are around 15 database tables. Since i will be using asp.net 2.0, I wont be able to use LINQ.I need to finish the development of the website in a very quick manner.How do i generate the data access layer automatically. I found NHibernate as one solution, but it seems too difficult for such a small project.
View 2 RepliesI was looking to build a Data Access Layer for my new web based application, I'm using ASP.NET. I'm want to build a framework not only for this application but also want to utilize it for my future projects.
Actually my main aim is to make a framework, from DAC, DAL, BL to GUI. I want suggestions from you guys that what should i adopt, what give me flexibility, which suits for both small and large size applications.
I'm building a Data Access Layer for my asp.net application. I would like to be able to share connection between different classes in order to manage transaction, but I don't know how to do that.
Example:
I have 2 classes, Order and OrderDetail.
I will call my DAL Order class for a SQL insert of a new order.
Inside the Insert method, I want to call my OrderDetail class to insert my order's details, and I would do that with same connection and transaction.
I keep all of my code in codeLib.cs and use it on various ASP.NET pages. However, I still have to do the databind(); in the code behind page for each aspx file. How can I eliminate all code in the aspx file so I just have the UI in the aspxand the code and databind(); in codeLib.cs.
View 4 RepliesI'm working on a DotNetNuke module in C#, and in order to cut down on the amount of complexity I have elected to try and keep the configuration of the module in one page (other than the standard Settings module). I now wonder how wise of an idea that is.My module is a simple image gallery, with one or many images. Each image has a title, an image source (url) and a destination (another url). Therefore, I figured that for my admin interface, I could have a simple 'grid' of data where you can edit all of the existing entries or add a new one, all on the same page, sort of like this:
Title Image URL Anchor HREF
[A Picture! ] [http://www.example.com/image.jpg ] [http://www.example.com]
[Another Picture!] [http://www.example.com/image2.jpg] [http://www.example.net]
[ ] [ ] [ ]
Looking through WebControls, I found the GridView, which at first blush seemed like the sort of thing I was looking for. However, taking a closer gander at it, I found that it needed to be bound directly to a data source, while it seems like the DotNetNuke standard of doing things in the Data Access Layer is to create a collection of data objects like so:
// EditDiscovery.ascx.cs
DiscoveryController objDiscoverys = new DiscoveryController();
List<DiscoveryInfo> lstDiscoveries = objDiscoverys.GetDiscoverys(ModuleId);[code]....
Is there something I'm missing with the GridView, or should I be changing the GetDiscoverys function to return a DataSet as opposed to a List of DiscoveryInfo objects? Or is there a better approach that does things that align better with DotNetNuke's DAL?
I am somewhat new to ASP.Net and the interesting ways to build forms that edit data. I am working on a FormView and have come to a hurdle that I can't seem to figure out how to get past.
This link will open the form and a dummy record where ID=2. [URL] ....
The ID is the variable to open a specific record. That's pretty obvious. Clicking the Edit button switches the FormView from ItemTemplate to EditItemTemplate. My problem is that after changing some values then clicking Update, the record is not updated.
I need to have the record updated and return to the ItemTemplate view. I believe there are issues with the fmvData_ItemUpdating and fmvData_ItemUpdated functions. I am not sure what has to go in there.
I also want the Inspection Date field to be formatted to mm/dd/yyyy when switching to the EditItemTemplate.
My TableAdapters are creating using the App_Code/DataSet.xsd method.
I am using Eval("fieldname") in the ItemTemplate for values and Bind("fieldname") in the EditItem template.
This is my Markup:
HTML Code:
. do you need to see these details? .
. do you need to see these details? .
This is my Code Behind:
Imports System
Imports System.Data.SqlClient
Imports System.Data
Imports System.Collections.Generic
Imports System.Diagnostics
Imports System.Configuration
[code]...
I am making use of 3-Tier architecture while making my project. And in Data Access Layer I am making use of application block, but application gets a connection string from web.config; but ClassLibrary of Data Access Layer doesn't contain web config file. How can I access connection string from Data Access layer?
View 5 Replies