Forms Data Controls :: How To Display Related Foreign Key Value In Gridview With Entity Framework
Oct 12, 2010
I have a gridview displaying "registrationtype id" (FK) from the registration table. I want it to display the related name instead of the id from the registartiontype table.
I am trying to add a new entity and have to refernce associated data to add it. I cannot load the Referencetables. Giving "The EntityReference could not be loaded because it is not attached to an ObjectContext." How do i complete this task in Entity Framework 3.5
I'm trying to insert a new EF object containing a reference to a related table via foreign key, and cannot get the reference stored in the new object. I have two tables in a SQL Server 2008 Database:
Component Templates PartGroups
with a Foreign Key linking them thus: ComponentTemplates:ID [0..1<->*] PartGroups:ComponentTemplateID
I have imported these tables into a .NET web application project .edmx file (using a new ADO.NET Entity Data Model), and then created a Data Service which I then reference in a Silverlight 3.0 project. The objects are available as expected in the data context called by my Silverlight app and load correctly. Now, when I try to save a reference of ComponentTemplate into a newly created PartGroup, the PartGroup object is created in the database, but the value of ComponentTemplateID in the newly created table record is NULL.
[Code]....
(Note that _ctCtrl.ComponentTemplate is a confirmed non-NULL object reference to the parent object on which PartGroup is a child)
1 - Is it necessary to have foreign key to obtain a Relation in Entity Framework between each entity.? 2 - I have a Language Table and many many table with a foreign key related to the language table. Is it right to add this foreign key or I should do something else ? Ex: Language LangID LangName
How can I give set foreign key value field in Entity Framework. I have Kartlar entity (related from kartlar table). I need simple save method this field but, RehberID, KAmpanyaId,BirimID is foregin Key....
public static class SatisServicesUpdateTables { public static void SaveKartlar(int RehberID, int KampanyaID, int BrimID) { using (GenSatisModuleEntities genSatisKampanyaCtx = new GenSatisModuleEntities()) { Kartlar kartlar = new Kartlar(); kartlar.RehberReference.EntityKey = new System.Data.EntityKey("genSatisKampanyaCtx.Rehber", "ID", RehberID); kartlar.KampanyaReference.EntityKey = new System.Data.EntityKey("genSatisKampanyaCtx.Kampanya", "ID", KampanyaID); kartlar.BirimReference.EntityKey = new System.Data.EntityKey("genSatisKampanyaCtx.Birim", "ID", BrimID); kartlar.Notlar = "hfhfhfhfhfhfghfghfgfghk"; genSatisKampanyaCtx.AddToKartlar(kartlar); genSatisKampanyaCtx.SaveChanges(); } } }
But it throws to me : ArgumentException was unhandled by user code link text
I developed and entity framework (.edmx) application in 4.0 in that i got all the data of my querying table and its foreign key referenced tables data also. but when i change my project to 3.5 i am unable to get the data of foreign key referenced tables data.
Adding data into kartlar table (RehberID,KampanyaID,BrimID) is ok. But which Kart'ID created? I need to learn which Id created after adding data (RehberID,KampanyaID,BrimID) into Kartlar?
[code]...
How can I do that? I want to get data from Kartlar which data I added?
i create example using Northwind database so i create a new website and add new ADO.Net Entity Data Model (.edmx) called Northwind.edmx and i add Categories and Products table inside this (.edmx) file
and add new ADO.Net Data Servuce called "ADODataService" and add it as WebReferences called NorthwindService
so i add new web page and drag DropdownList and Gridview as i want to bind Dropdownlist to all categories and when i select category from Dropdownlist bind Gridview to all Products related to this category
so my code
[Code]....
and my code [Code]....
so when i select category from Dropdownlist nothing happen :(
also you will find commented code in method BindCategory whuch is not work also.
I m try to insert record to table, its working well without foreignkey using Entity model. But i need to insert foreign key. I used the following query, its not working well via Entity model.
objFacility.FacilityCategoryReference.EntityKey = new System.Data.EntityKey("testEntities.test", "id", 10);
I am using Entity Framework for my .NET application. I have been able to return objects and their directly-related objects as well (very convenient), but I am having trouble getting the objects of those objects.
IEnumerable<Lot> i = (((ObjectSet<Car>)_carRepository.GetQuery()) .Include(a => a.CarTypes).Take(10).ToList()
This works and I can access carTypes, however I cannot figure out how to access tables associated with CarTypes (e.g. tables which have fields associated with the car types). I tried to use a Join however I was unable to figure out how to get it to work right.
I use VS 2010 Ultimate. I created an 'asp.net web application' from scratch, added a 'ADO.NET Entity Model' to my project (EF4).
The problem I'm having is that whenever I try and use an EntityDataSource to pull data out of my entity model I am near constantly getting the following error:
"The metadata specified in the connection string could not be loaded. Consider rebuilding the web project to build assemblies that may contain metadata. The following error(s) occurred:"
how to handle foreign keys with Entity Framework, when editing or adding a new record. For example, I have a person table, which has a timezone_id linking to my timezone table.
But the model seems to not include timezone_id. I see it's a new way of doing things, but ... how do I store my record?
My method:
[code]...
I can't do u.timezone_id = timezoneid;
I only have u.timezone (which seems to be the actual entity), and u.timezoneReference, which I am not sure what to do with.
i want to display name of related table in my gridView insetad of it's id. one solution is using sqlDataSource or objectDataSource, but i don't want using this appproach. i want to do this without setting any dataSourceID or join tables, in other word, i want to do this like windows form datagridViewComboBoxColumn.
I would like to display students and their grades with a GridView and LinqToSQL like this:
[Code]....
I found this topic but it doesn't answer my question: http://forums.asp.net/t/1557987.aspx
I have a many-to-many relationship between students and assignments called "grades".The grade for the assignment is stored in that table in a "gradeNumber" column.The many-to-many relationship seems to be a problem.I tried adding a TemplateField to my grid:
[Code]....
It doesn't work: ...student does not contain a property with the name grade.
It does work when I use class.name however to get a student's class he is in.In code students .grade[0].something works however My LINQ entities are extended with custom code to allow me to retrieve studentx.Assignments or assignmentx.Students.(I would also like to specify which assignments should be displayed in the grid.)
I am new to Entity Framework and working my way through it little by little. I think I have it figured out on how to get data into and out of 1 table at a time now the challenge is 2 tables into a gridview. I have a user table that has a list of threads that a user can mark to track. Easy enough. Assign the userid number & threadid to a table with a push button while the user is logged in and viewing any of the posts that are on that thread. The new challange is to get only the posts that the user has marked to track. SQL easy. Entity not sure what to do.
If I make a view or stored procedure and add it to the database that would be an extra step. To join the 2 tables as in sql Select posts from posts where track.userid = @userid join track on post.userid=track.userid Seems Entity was made to avoid this type of thing. Than once the data is gathered I need to bind it to a gridview()
I've a gridview with 6 coloums. First col is dropdown list and rest are text boxes.aspx page looks like this
[Code]....
I've a created a class and bounded to grid view in my Business LayerThe dropdown list was bounded to another table by using gvExpense_RowDataBound eventNo.of rows in gridview depends on no. of rows in expensetype table
I am working with entity frame work to insert data into data base for that I write a web method and query function but data can’t insert data base following my function and web method.
///////////////////////// function AddGridviewData() { var AddRow = new Array(); $('[id*=Test_gridview]').find('tr:has(td)').each(function () { var NewRow = {}; NewRow. name = $(this).find("td:eq(1)").html();
[Code] ...
There are no error and no insert the data into data base.
I've created a new ASP.NET website. I've generated an Entity Data Model from my database and have dropped a entitydatasource and gridview onto my page and wired up the gridview to pull from the entitydatasource. Now I get columns like this: id extension prefix did_flag len ten_id restriction_class_id sfc_id name_display building_id floor room phone_id department_id
In each case where the item is named something_id this reflects a foreign key relationship in the database - and I did choose to have the EDM expose foreign key relationships. I'd like to make it so the gridview pulls in the values for these foreign keys rather than just showing the ID numbers - so, for example, department_id might have a value of "101" right now but it should pull from the department table "Marketing".
Is there a way to export a EF 4.0 Data Model to EF 3.5?
I looked around and found that we are not able to access EF 4.0 from a ASP.Net 3.5 project here: [URL]
Our project is the 1st to go to .Net 4.0 using Entity Framework and we (the team) were wondering if there was a way for the other projects that "might" need to access our data that are still using the .Net 3.5 framework.
I have a search button ..The result will be displayed in grid view if the button is pressed .. i am able to do it
But now i want to do like this ..that is my grid view is only displaying the ResultId .. I want to display the ResultName rather than resultID in the table
I use a Detailsview, Entity Data Source to edit/update my table with only 3 columns.(it has primary keys).
Everything works fine inserts/edit in dev environment. but when i run this in release mode. i cannot update existing data in the database with the detailsview. whenever i update and save page gets refreshed, but nothing gets updated. but whenever i insert a new record, and then i try editing it. it works.?
Note: i handle DetailsviewItemUpdating,DetailsviewItemInserting events to do some custom checks.