DataSource Controls :: Gridview Using LINQ To DeleteOnSubmit?
May 28, 2010
I continue to get compiler errors. I have a Gridview (with Delete and Edit buttons) that I populate via LINQ with e-mail addresses. When they hit the delete button I want to use LINQ to delete the row from the table based on the GridView DataKey. If I use Response.Write(ID) it will show the ID number for the Email that I want to delete.Here is the error:
"Error 2 The best overloaded method match for 'System.Data.Linq.Table<Email>.DeleteOnSubmit(Email)' has some invalid arguments C:InetpubwwwrootXXXXXXXXXEditEmail.aspx.cs 53 13 C:...XXXX"
I want to display a Gridview of Patients before I submit them to the database. Is there a way(better way), other then List<Patients>, to bind a list to a GridView.
I am using Linq to SQL and I have a DAL with the Patients table inside. I create a new list of Patients
[Code]....
Now the problem is I can't use a Linqdatasource or Objectdatasource to link to the GridView as no data is in the db yet. The only thing that works is GridView.DataSource = _patients; but I lose all automatic formatting and as far as I can tell it is going to be a pain to format manually. It would seem I should be able to somehow link my object _patients to an one of the datasourses so I would have formatting and all.
Both the Method 1 and Method 2 can handle the paging of GridView, could you tell me how about the performance of the Method 1?and how much will Method 1 slower than Method 2
#region ForPaging public static List<HD_ToDoList> Get_ToDoListByUserNameForPage(string username, int StartIndex, int PageSize) {
I have Gridview control which bind data from LINQ datacontext object which use store procedure. sort the gridview using LINQ datacontext object which use store procedure.
I have a database table column consisting of text URLs [URL] In my LINQ-to-SQL-driven gridview, I want to make this a clickable link programmatically, with differing link text (e.g. "Link text"). I'm getting close but am missing some key concept. Here's the core of the .vb codebehind:
Dim dctx As New ResourceMod.ResourceModDALDataContext Dim eleResObj = From eleRes In dctx.Resources Where eleRes.Type = "url" Select siteurl = eleRes.Website GridView1.DataSource = eleResObj GridView1.DataBind()
This displays the raw URL in the gridview (i.e. non-clickable). I've experimented with adding an explicit hyperlink column a la [URL](setting AutoGenerateColumns false etc.), but haven't yet figured out how to assign the asp:hyperlink Text and NavigateUrl fields with the anonymous-type object eleResObj. Using a field construct such as Text='<%# Eval("siteurl") %>' isn't working, presumably a scope issue. Is a LinqDataSource needed in this case, and if so, how would that affect the original LINQ query?
I started learning LINQ, So i thought of just creating gridview with sorting and paging using objectdatasource using LINQ. So i got this link
[URL] which Brian Orrel tell us how to do using IQueryable Interface. but i have nearly 300 lines of stored procedure which joins nearly 20 tables. so i thought of creating a stored procedure and using that instead of IQuerytable.
I am writing a plugin to help with a current ERP system we have that I am not allowed to modify the data structure at all. The table I am dealing with has over 100 columns and I am wanting to set my linq object propertychanged event and submitchanges or do I really have list out each property and set it equal to the new one?Below is an example of what I am trying to do:
Like that I have large number of controls on my form. I have dought, if I assigned like this, db.usp_ATI_FetchPatientDetails(iPatientID).ElementAt(0).Last_Name.ToString(); to every control, then I have set of controls like,
My question is that, for each control the Stored Procedure called or not? If it is yes then it is time consuming and I need to use LINQ to DataSet or LINQ to Object rather than to call SP for each control. What is difference between LINQ to DataSet and LINQ to Object?
I am looking for a way to do paging with a GridView when i set the datasource at run time using a linq query. here is my code:
ETDataContext etdc = new ETDataContext(); var accts = from a in etdc.ACCOUNTs orderby a.account_id select new { Account = a.account_id, aType = a.SERVICEs.FirstOrDefault().SERVICE_TYPE.service_type_desc, name = a.SERVICEs.FirstOrDefault().service_name,
[Code]....
But that works well when you use a datatable but not with linq. If I add a rebind in the event, it has to requery 7000 records which can be a little slow. Does anyone know how to fix the paging when using linq like this?
public IEnumerable<Customer> GetCustomers() { Table<Customer> custObject = context.Customers; IEnumerable<Customer> filteredCustList = from customer in custObject select customer; filteredCustList; } GridView2.DataSource = utilLinqClass.GetCustomers(); GridView2.DataBind();
(no errors at build time or at compile time) Error I am getting is: An attempt to attach an auto-named database for file App_Dataaspnetdb.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
I am trying to use a linq query to create a report and I am unclear on how to traverse the linq dataquery in my case. Inside my for each loop, i have a do while loop. The way it is written below, the do while loop is infinite because I never skip to the next itm in oneSchedule. Placing a Next inside the do while loop causes a syntax error. So what is the correct method for moving to the next itm within the loop?????
select * from MyTable select "MonthName"= case when datepart(month,date1) =1 then 'January' when datepart(month,date1) =2 then 'February' end , count(*) as CountByMonth from venkat group by datepart(month,date1)
I'm trying to "move" a LinqDataSource control to code behind to better control the query parameters. Problem I'm having is how does the "It" keyword translate to Linq To SQL syntax (not sure if I'm getting the terminology right here, but I think you get my meaning).
If I have an ID, I would like to retrieve the next item that also has the same category as the item ID I have. So, for example, if I have ID=2, I would like to return the item with ID=4 (as item ID=3 has a different category).
Whenever you want to implement Linq to SQL on a project there is inevitably a battle between the DBA and the developers over it.
From the developer standpoint, Linq to SQL eliminates the need to manually write stored procs, ADO.NET data access classes, business object classes, and datatable -> business object conversion classes. This makes development a breeze and eliminates a lot of the traditional layers that you'd normally have to code.
Alternately, from a DBA perspective there are some issues. One is that a lot of DBA's like to do security at the sproc level, and this level would be gone. Another issue is that if the DBA wanted to mimic some sql functionality that the application is doing, possibly for a scripted action, they wouldn't be able to simply call the sproc that the application is using. Also they wouldn't be able to tell which columns are actively being used and which are not, as it'd be C# code specifying which columns are returned rather than sprocs. Lastly, if something needed to be changed structurally, it'd require a recompile and redeploy of the entire app rather than a simple sql script of 2 being deployed.
There are valid points on both ends, so I'm wondering what experiences you all have with this and what sort of compromises you made. In my situation, I'm the developer and I'm trying to figure out a compromise I can make with the DBA so we both give a little rather than one of us having to completely bend over. The obvious compromise to me is using sprocs from within Linq to SQL, but it adds another layer of development and the sprocs have to coded a certain way to play nice with Linq to SQL.
SELECT * FROM dc.accounts t1 INNER JOIN dc.profiles t2 ON t1.AccountID = t2.AccountID WHERE EXISTS ( SELECT * FROM dc.profileblocks t3 WHERE t3.AccountID = '14' and t1.AccountID = t3.AccountID )
I'm close to the solution I see where I am going wrong just unsure how to approach it. I want to be able to take a tables worth of data (via DataClasses) and put it in a CSV to download.
A LINQ to SQL query is performed (basically a 'Select All' from tbl_Newsletter), takes those results and the idea is to feed those results, one by one through the foreach which, inside it, is the CSV's definition e.g. List.Add(etc) as you'll see. After which the CSVExporter method is called - which works, as I can Download it, it just wont display any results.
C#: [Code]....
To which I get: Compiler Error Message: CS1729: 'Newsletter' does not contain a constructor that takes '2' arguments
with Newsletter obj = Newsletter.GetAll(); in place of Newsletter obj = new Newsletter();
I get: Compiler Error Message: CS0029: Cannot implicitly convert type 'System.Collections.Generic.List<Newsletter>' to 'Newsletter'
