My goal is to load a row from db to a webform and let the user update it's value .
The user searches an id (i have a stored procedure for that), how i show that data from the
row nicely in the web page through the dal layer. After the data is shown on the page the user need to update a cell in the row and send it.(the part of updating is not the problem).
in other questions how should the dal method should look and how i integrate it's result in the presentation layer (the aspx webform).
thanks a lot.
p.s.
I've done a little reading but i don't know what exactly to use data object, data row , data table, object data source. i'm little confused by the data bind alternatives.
You have several options and one of them is using ObjectDataSource.
If it is going to be a single record you can use DetailsView or Formview else you use GridView.
Check the tutorials here:
Displaying Data with ObjectDataSource
Data Access Tutorials
Related
[Thanks to Filburt and Devjosh. I have restructured the post and included my attempt approach. ]
I have a table on my SQL DB call ReportList which is a list of report. I need to go through that list and interrogate the reportserver, eport by report, to populate a table called ReportParameters. The ReportParameters table has a column for ReportOwnerID which needs to contains the ReportID value of the corresponding (owner) report as listed in the ReportList table.
This is in VB.NET 2005 ASP2.0 and I have ended up with a mess. Please help me with the cleanest approach to doing this.
It needs to work so:- I have a listbox of the reports as per REportList and a GridView that list all the parameters (uniquely - most of the parameters are common to many reports) the idea being that the parameters get set once and the report can be kicked off by selecting them in the ReportList CheckListBox and clicking on Execute.
I would like it that as I click on a particular report in the ListView, the relevant parameters in the Gridview get a green background and those that do not apply are red. The leftmost column in the gridview contains tha Parameter NAME (not editable) and the next column must be editable to populate the value.
DONE SO FAR:
I have tried on clicking the EXECUTE button , to build a parameters string in a testbox and call that with the Javascript OpenReportWin() function when I open the report in a new window. This works fine, but my biggest issue it interrogating the reportserver reports to get back a list of parameters and dooping them into a table. I have triend to use a hidden DataGrid bound to a ds onto the reportParamaters table; I have tried to poulate it using a datalist but I cannot get the hang of these thionsg and its looking messy. Ther must be a simple clean way of gettting the .GetParameters resultset back from the report server and populating the table without having to create a reportviewer object and cycling through the list of reports - it then has to render each report before you can get that list out.
Thanks
I will withdraw this for now. I will submit a solution when I am comfortable that I have reahced a clean solution.
Mac
PLEASE CLOSE!!!
I have a GV and a DV that extract data from the same database. The link between these controls is when a record in the GV is selected, the DV displays more details about that record.
Do I need separate connections? Obviously, I haven't achieved this goal and am working on it. Thanks.
CLARIFICATION so as not to waste your time:
I am asking about connection, not datasource. The reason that I am not sure the same connection can be used is that with GV, the connection doesn't have any parameter. Whereas with the DV, it needs the record ID passed to it. Or am I wrong?
Here's the link to code on the net that makes me wonder:
http://asp.dotnetheaven.com/util/srcview.aspx?path=~/aspnet/samples/data/GridViewMasterDetails.src
I am a novice so am still confused with the terminology. Thanks for being patient.
They can use the same datasource. (Such as an ObjectDataSource or SQLDataSource)
You can use the same data source, i.e. a DataTable. But when the Gridview row is selected you will need to find the index of the selected row and then find the DataRow from the DataTable and rebind your DetailView to that DataRow. Hope this helps.
I think that you are using Visual Studio databinding, and I would say that same Connection(DataSource) object can be used (if that is the way it goes), but I would rather suggest you avoid this design time Visual Studio programming, although it is simple and fast
Hi I am new to using ASP.NET and GridView and it would be great if someone could kindly help me out here.
My scenario is that on a button click event, my code tries to get data from a webservice in chunks for a long period of time. Now I create a DataTable and populate it as each chunk is retrieved. My question is how do I show in gridview whatever I have retrieved so far before the button click returns ? Say, if I have three chunks being retrieved one after another then as of now the gridview gets populated with all the data from the 3 chunks at once, I want to be able to show the first chunk as it is downloaded, then add the second chunk and finally the third. Not sure how to do this.
I'd be happy if you just give me an overall solution/point me in the asp feature I should be using to get this done. Thanks.
If you are binding using webservice. Then asp:GridView will create unnecessary hassles for you as its designed for simple server side bindings.
Why dont you try DataTables or jqGrid, as they are much better alternatives?
You can Merge the existing DataTable every time you receive a new chunk from the Web service and then bind the updated (Merged) DataTable to the gridview.
Check out this article from MSDN and get a better idea of how you can merge DataTables
DataSet.Merge Method (DataTable)
Also look at this article that may help you in your current problem.
Merging two Datasets into a single Datagrid
Using the ASP.NET grid view. It displays 3 columns with 1 row for each, displaying an integer saved in the database. I would like to have a text input one for each column, so the user can add a new row of integers to the database. (The table only displays the last row updated, that part seems to be working OK)
Here is the code I have that displays data but without the input option I would like.
What is the way this is done in ASP.NET (3.5)? Are there more options in the control or do I need to manually bring in text input controls and give each one manual code to update the database? Any help is appreciated.
Thank You.
Do you know the asp.net website? There are a lot of tutorials, e.g. about data access. You might find the information you need, e.g An Overview of Inserting, Updating, and Deleting Data.
Also check out the ASP.NET Dynamic Data section on the same page.
I have been tasked with sifting through the worst classic asp spaghetti i've ever come across.
The script runs a series of recordsets in sequence, getting 1 record at a time. As the record is built it takes the id and passes it to the next loop, which gets data, and passes on the id to the next loop. It then continues in this manner and builds an unordered list, kicking out the required html as it goes.
Here are my efforts so far:
have a class delivering data via sqldatareaders and output these to nested repeaters (this failed due to not being able to loop and get the id)
Have a datatable populated with all the required data, then datatable.select to filter it out.
have 4 datareaders looping and building the ul arraylists (I
couldnt get the id's to match up)
Please can you suggest the best method
Yes of course it can be rewritten in ASP.NET - note that i said rewritten, not just refactored, there is no saving that code (which is okay for what it does, but things are different with ASP.NET).
To be honest, i didn't even check the code, it hurt my eyes. A lot. But in general you can use a nice SQLConnection object, and a SQLCommand, call a stored procedure and get a nice SqlDataReader full of data from which you can build a DataTable or an IEnumerable list of data objects. You then have a repeater type control (ListView, GridView etc) in the UI, simply by binding your datatable or list to that control will render the results.
With the ListView, you specify a template for each data item that is rendered. For a GridView you specify the columns (or column templates) and which properties on each data item the columns should bind to.
When you retrieve the data, you can leave it as a DataTable, or translate it into something else like a list (or array) of data objects. As long as your list/array implements IEnumerable you should be able to just assign the list to the ItemsSource property of the aforementioned repeater control and it will perform its magic.
You don't even have to use a SQLCommand and DataTable object - you could even use Linq to SQL and bind the results straight to your repeater control.
This is just a high level overview of how you could do it, there are a couple of different ways. Once done, your code is going to be way cleaner and more maintainable than the classic ASP code.
Edit: your main issue is how to produce an ordered list, which is what the current code is doing with its nested loops supplying IDs for the detail items.
I would suggest you take a step back, and rethink the sql. In fact, throw the current sql away, it is incredibly inefficient with the tools you have today. It takes literally tenths of a second, and just one database call to return a flat table of data. Your first instinct may be "but i don't want to return too much data!" - relax, even returning several thousand data rows can be a sub 1 second operation if done correctly. You can also restrict the returned data by passing parameters in to the stored proc, or appending them to the dynamic sql statement that you construct (although it pains me hugely to mention dynamic sql, i think it is evil, but some people still use it - i would not recommend it unless it was your only option). To sum up what i am saying, how your data is returned from the database and how it looks on screen are two different things, don't let one guide the other. You can get the data from the database, then manipulate it before rendering it to the UI.
If you still want to show the data as an ordered list, then use a ListView, define a template for each data item, then you can use LINQ to group or filter the data you like (the data item template can contain whatever HTML or ASP.NET controls you like, and that template gets rendered for each data item in the list of data). Alternatively, you could use a GridView, and then use the grouping capability of the GridView to do the work for you - just specify which column(s) you want to group on, and the GridView takes care of the rendering.