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'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 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 RepliesAre there scenarios where it makes sense to encapsulate a data access layer (of a ASP.NET webapplication) with WCF or WCF Data Services ? Makes it sense to use a service inside the application ?
View 2 RepliesI 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 RepliesI've been attempting to walk through the "Creating a Data Access Layer" tutorial found [URL] I create the DB connection, create the typed dataset and table adapter, specify the sql, etc. When I add the code to the presentation layer (in this case a page called AllProducts.aspx) I am unable to find the NorthwindTableAdapters.ProductsTableAdapter class. I tried to import the NorthwindTableAdapters namespace, but it is not showing up. Looking in the solution explorer Class View confirms that there is a Northwind class, but not the namespace I'm l ooking for. I've tried several online tutorials that all have essentially the same steps, and I'm getting the same results.
View 1 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'm having a difficult challenge of passing a DropDownList Selected Value to a Data Layer having a Function containing 'cmd.Parameters.AddWithValue("@CourseDDLid", CoursesDDL.SelectedValue.ToString)'. Visual Studio is indicating I need to declare 'CoursesDDL'. I tried accessing the 'Find Control' method but it did not work. Below are the codes for your review.
[Code]....
Iam facing the problem with creating the Data Access layer using Dataset.xsd file and How to access the data from the file.
View 2 Replieshow to delete from detailview without using datasource?
And it also doesnt work using sql datasource .
From my Employees table of the Northwind database, how do I delete a row? I have a row with a LastName field = WWWW How to write the string sql?
SqlConnection con = new
SqlConnection(connectionString);
string sql =
"DELETE FROM Employees WHERE LastName =" + WWWW;
SqlCommand cmd =
new
SqlCommand(sql, con);
I'm looking for ideas on deleting data from the multiple SQL tables with LINQ (C#).
My existing solution does the following:
1. DeleteAllOnSubmit( Subset of the data from the child table)
2. DeleteAllOnSubmit( Subset of the data from another child table)
3. DeleteAllOnSubmit( Data from the parent table)
4. CommitChanges()
All this resides within a single method, which makes it ugly and not re-usable.
I have considered the following alternatives, but I decided not to use them:
1. Cascade delete on the tables.
2. Do a join on all tables from which I will remove the data, but I'm not sure yet whether I could pass a join query to DeleteAllOnSubmit().
3. Write stored procedure(s) to delete data from each table. I don't have the time to implement this due to a large number of tables and the time constraints.
I'm using the asp.net membership on my website. On the User Administration page i've got a GridView to show the details of the users on the site. As a datasource rather than just using the Membership.GetAllUsers function i've got a SQLDataSource as i need to display user information from 3 different tables. I'm trying to add a delete button to the GridView. I'm setting the Membership's UserName as a DataKey and then using the RowDeleting event to call Membership.DeleteUser for the appropriate UserName. This works fine and the user is deleted however i then get an error showing up that "Deleting is not supported by data source 'SqlDataSource1' unless DeleteCommand is specified."
I don't want to use the SqlDataSource for deleting as i've already done it using the Membership. How can i stop it from trying to do this? Here is the cut-down that i have if you're interested. The selectcommand in the sqldatasource was auto-generated by it.
[Code]....
In 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 Repliesi have problem white Object datasource. i have a multi-tier Application that include common layer ,DAL Layer,business logic and persantation layerwhen i add a object datasource to my page, it bring me only common layer classes . but i want use bisuiness layer classes what do i do ?
View 1 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 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'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]....
when I press the delete button on my girdview, I want to get the [Path] filed value of the deleting data row In VB code. How could I do that ?
View 2 RepliesI have a DataGrid that I need to be able to use to delete records form a file
[Code]....
[Code]....
I use
((TextBox)GridMenuOptions.Rows[e.RowIndex].Cells[1].Controls[0]).Text;
To access the data in the Grid for updating, but it doesn't work for deleting
I can use
string id = GridMenuOptions.DataKeys[e.RowIndex].Value.ToString();
but that only returns the first key.
How do I access the rest of the keys?
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 Replies