I have generated entity framework designer classes . After Generating the designer what is the most nicest and cleanest way to apply data annotation to the properties there . I have 3 classes there
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I have a problem with strange generate sql in ef4 ctp5. I have simple model with mapping :
[Table("post_auction")]
public class PostAuction
{
[Key,Column(Name="Id"),DatabaseGenerated(System.ComponentModel.DataAnnotations.DatabaseGenerationOption.Identity)]
public int Id { get; set; }
[Column(Name = "Number")]
public int Number { get; set; }
[Column(Name = "Label")]
public string Label { get; set; }
[Column(Name = "Description")]
public string Description { get; set; }
[Column(Name = "CategoryId")]
public int PostAuctionCategoryId { get; set; }
[Column(Name = "PriceCZK")]
public int PriceCZK { get; set; }
[NotMapped]
public bool IsAuctionPhotoExitst
{
get
{
if (File.Exists(HttpContext.Current.Server.MapPath("~/Public/Images/Posts/Thumbs/small_" + this.Number + ".jpg")))
return true;
return false;
}
}
}
and my linq query is :...............
Is there a method like IsValid(); in Entity Framework Generated classes?
Would I have to create a method like the above?
PS.
I would like the method to return a boolean.
Technically I have the Data Annoations working with Linq to SQL classes - the problem is when validation
passes. When UpdateModel() tries to do its thing i can an error:The model of type 'MyProject.Models.Employee' could not be updated.What i did was i created a partial class for Employee (that is generated by linq to sql), then stuck a Meta Data class on top of it for the validation
[Code]....
And in my master page i include
<script type="text/javascript" src="/Scripts/jquery.validate.min.js"></script>
I am using below code to get new inserted ID in auto identity column from database.
[code]....
It's working fine when I connect my application with MS Sql, but if I connect with Mysql, it always returns 0 (zero).
Is there any other way to get last inserted ID using Entity Framework?
I have a "database explorer" page that is desgined to be pointed to an unknown database and allow users to browse the data, so it basically uses the SQL system tables to develop its queries and pull in data to tables using auto-generate columns.The problem that I have is that I would like certain types of columns to have certain formats and I'm wondering the best way to go about it. I could format the column in code in the RowDataBound event I assume, but I'm wondering if there some better standard way to do this? Is there a setting of any kind that I can use? For example I want all of the datetime fields to be formated for short date, like {0:d}, I want decimal fields to have 4 decimal places, etc.
View 2 RepliesIs 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 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
[Code]....
I would like to make some changes to my EF4 edmx file without modifying the file itself, mainly so I don't loose all my changes if I regenerate the model from the database. I'm familiar with XSL and have seen references made to using it in conjunction with the edmx file. This sounds like a great solution, however I can't seem to find any documentation on how to actually set this up. Do you reference the style sheet from the edmx file or do you configure it to look at the template and then load the edmx file in somehow?
Clarification:
Specifically what I'm trying to do is modify the model so that several of the views act as tables with relations within the model, see here: http://blogs.msdn.com/b/alexj/archive/2009/09/01/tip-34-how-to-work-with-updatable-views.aspx
The issue I'll have in using that method is if I need to update the database and regenerate the model I'll have to go back and make all of those changes again, I was hoping there was a way to use xslt to make those changes to the views so they would not be removed when the model is regenerated.
I transfered my data from MDF files to MS SQL Database, but I can't get it working with entity framework.
My Old connection string is:
metadata=res://*/Models.EntityModel.csdl|res://*/Models.EntityModel.ssdl|res://*/Models.EntityModel.msl;provider=System.Data.SqlClient;provider connection string="Data Source=.SQLEXPRESS;AttachDbFilename=|DataDirectory|TripsDB.mdf;Integrated Security=True;User
Instance=True;MultipleActiveResultSets=True"
I put all data from TripsDB.mdf to Trips table in local MS SQL 2008 Enterprise database. Also changed connection string to:
Server=WIESIEK;Database=Trips;Trusted_Connection=True;providerName=System.Data.SqlClient;User ID=Jan J. Roman
But my application throws System.ArgumentExceptio with message: The 'server' keyword is not supported.
on line:
private TripsDBEntities2 _entity = new TripsDBEntities2();where TripsDBEntities2 is Entity Framework instance.
I am new to entity framework , it is really very good , but I want to know what is the difference between using entity framework with stored procedure or without stored procedure , which one the faster and what is the benefits for using stored procedures with entity framework.
View 1 RepliesI have an EDM, it includes the entities extension and history. My goal is to use history to keep track of all the changes made to extension entity. For example, if extension with ID 223 has its property 'Name_Display' changed - I want the history entity to record this.
I'm using ASP.NET with VB.NET. Where in my code do I put the hook to say, "update the history entity" and what should that hook look like?
I am using asp.net grid view which has is populated dynamically that means it has auto generated columns at run time.
I just want to know db type of these columns whether a column is text , date or int type.
I am currently working on a module in which I am creating an auto generated column gridview, and I have set the Auto generate edit button field to true. What happens now when I click the edit button The primary key field is turned in to edit mode which I want to restrict from being updated.
To restrict the same I have hard coded a template field which holds that column, But as I have set the AutoGenerateColumns Property to true the gridview automatically creates a duplicate field for holding the primary key column. For which I want to delete that particular column.
My Designer Code is:-
[Code]....
in page load I am binding the grid view.
Even I have tried to hide that column doesn't make any difference for me.
I have a gridview which has autogenerate Columns Property "TRUE", and i'm dynamically binding this gridview with columns with sql database dataset. there is no data in sql but i am successful in showing blank gridview on form, now i want textboxes in gridview attached with each column, so i wrote code in RowDataBound which generates textbox automatically and assigns ID to each textbox, nw i want to insert that data from textbox to database but i'm not getting text which is entered in those textboxes, as i am accessing that textboxes using findcontrol and passing the id like gridview1_ctl03_text0. but i''m not getting any value from textbox?
In short i want to access auto generated textbox (with out any id predefined ) values from footer of gridview
is there anyway to set gridview autogenerated column width
View 2 RepliesCurrently, I am programming a web-based application with Visual Studio.NET 2003, and having a problem with an err below :
An error has occurred because a control with auto-generated id 'dgPreventiveMaintenanceSchedule:_ctl5:_ctl3' could not be located to raise a postback event. To avoid this error, explicitly set the ID property of controls that raise postback events.
That err occurs while I am rendering my datagrid for certain data. In the other words, it occasionally happens.
I've been trying to debug one by one, but I still don't any clues for this kind of err.
Is there any way to disable autogenerated edit, delete buttons in gridview. As they don't have names to use find contro, how can I find the edit button in the row and disable it and enable when required.
View 5 RepliesI have a gridview which makes use of a datasource. The columns are auto-generated.
Right now, my task is to make the first column into a url column. Does anybody know how to do it?
i am using asp.net 4.0
i want to remove Auto Genrated Columns of Gridview at Run Time and change the header text of these columns.
[Code]....
Background: I'm populating lots of asp.net c# GridViews and ListViews from a database and subsequently users may export them to Excel. I want export as native Excel (not html). I can't use office automation, and I'm using JET which works fine. I have no control over users' machines. Question: When doing the export, you have to tell Jet what type each field is, in my case "text" (varchar) or "numeric" (double). The difference is that if you export a numeric column, the users can sum the data in Excel, where as strings are exported with a leading apostrophe and so are not much use in arithmetic.
Currently I parse the first data row of the Grid/ListView, check if each value is numeric or text, and assign a type to the column accordingly. That works, except for when I have something in the first column which looks numeric but in fact is a text string. I don't want to parse every row in order to be sure I have the correct data type as some of these exports are quite large. When I load the Grid/ListView from the database, the database certainly knows what type each field is. So my question is... how do I extract the type of the database item behind a a Grid/ListView item? I could explicitly code it as an attribute on the item, but that's duplicating information I already have, if only I can get to it. I know that where I have a DataTable then I can get the underlying type from that, but mostly I don't have tables handy, just the Grid/ListView. Note that Jet will throw if you try to insert an empty string into a nullable numeric column. The way to do this is to omit that column name from the insert statement, or output a zero.
I would like to inquire about the delete the data in gridview with automatic number parameter ..when I edit a field with auto parameter number, how do I delete a field that does not automatically sort ..ex:
1. ROBERT
2. EMILIA
3. JOSE
When I remove the column to 2 EMILIA, then display in gridview 1. ROBERT 3. JOSE.
Coding that I got when I remove emilia then display in gridview 1.ROBERT 2.JOSE .. (sequence automatically)
private void Bindemptydt() {
//Declare a datatable for the gridview
DataTable dt = new DataTable();
//Add Columns to the datatable
dt.Columns.Add("COLUMN");
dt.Columns.Add("TEXT");
[Code] .....
string attachment = "attachment; filename=Report.xls";
Response.ClearContent();
Response.AddHeader("content-disposition", attachment);
Response.ContentType = "application/ms-excel";
StringWriter sw = new StringWriter();
HtmlTextWriter htw = new HtmlTextWriter(sw);
GridView1.RenderControl(htw);
Response.Write(sw.ToString());
Response.End();
The above code exports gridview1 data to excel, but the requirement is export data with row no as first column in Excel. I tried to add row number in dataset that binding to gridview, when we sort data in gridview, row number are not in correct order.
I get an cast exception when i am trying to insert an entity in Entity Framework (using code-first). From this code :
public virtual T Insert(T entity)
{
return Context.Set<T>().Add(entity);
}
The cast exception is like "impossible to cast ...Collection'1(Entity) to type (Entity)" I can't figure out why. I am pretty sure ive done everything right. Post entity
public class Post
{
public long PostId { get; private set; }
public DateTime date { get; set; }
[Required]
public string Subject { get; set; }
public User User { get; set; }
public Category Category { get; set; }
[Required]
public string Body { get; set; }
public virtual ICollection<Tag> Tags { get; private set; }
public Post()
{
Category = new Category();
if (Tags == null)
Tags = new Collection<Tag>();
}................................
I am mapping a stored procedure to an entity by right clicking on the entity (in the .edmx) and selecting "Stored Procedure Mapping." This brings you to a Mapping Details - "Name of Entity" Window that allows you to select the insert, update, and delete stored procedures associated with the Entity. It also maps the stored procedure parameter to the Entity "Property" (Column).
I'm gettin an error "error 2042: Parameter Mapping specified is not valid." The cause of the error is fairly obvious, in the Insert stored procedure that has been selected, a 'CHAR' parameter is being mapped to an Int32 Entity Property. I altered the stored procedure parameter to match the entity, I deleted the stored procedure, readded, and reslected it as the Insert function. I also cleaned, validated, updated model from database. No matter what I do, the parameter list in the mapping details doesn't reflect the change to the stored procedure. It's stuck on a char --> int32 mapping, even though it has been changed, like it's buried deep in meta data some where.
