ASP.NET Dynamic Data

Re: ASP.NET Dynamic Data + guid

bignbullish — Fri, 23 Oct 2009 10:33:55 GMT

A better approach would be to use the Extensibility method .... "OnValidate"

    [MetadataTypeAttribute(typeof(Subject.SubjectMetadata))]
    public partial class Subject
    {
        partial void OnValidate(System.Data.Linq.ChangeAction action)
        {
            if (action == System.Data.Linq.ChangeAction.Insert)
            {
                this.Id = Guid.NewGuid();
            }
        }
        
        internal sealed class SubjectMetadata
        { ..... }
     }

Re: ASP.NET Dynamic Data + guid

suicidesquad — Wed, 27 May 2009 14:10:19 GMT

~~SjNaughton pointed me at the following solution:~~

*Solution*

To get the GUID as primary key saved and invisible I just added this code for every entity:

namespace DynamicDataEFProject
{
    [MetadataType(typeof(ActionsMD))]
    partial class Actions
    {          act_ActionID = Guid.NewGuid();
    }

    partial class ActionsMD
    {
        [ScaffoldColumn(false)]
        public object act_ActionID { get; set; }
    }
}
Now it generates the new Guid on insert and provides it to the database.
 
Do not add the setting "StoreGeneratedPattern="Computed" or StoreGeneratedPattern="Identity" in your model.xml in this scenario, because this entity parameter is an identity with type GUID.

Re: ASP.NET Dynamic Data + guid

suicidesquad — Wed, 27 May 2009 09:11:13 GMT

To disable scaffolding of specific column I created the following class:

namespace DynamicDataEFProject
{
    [MetadataType(typeof(ActionsMD))]
    partial class Actions
    {
    }

    partial class ActionsMD
    {
        [ScaffoldColumn(false)]
        public object act_ActionID { get; set; }
    }
}

The textfield is indeed not created anymore.

But when I do an insert I get one of these 2 errors:

When I add StoreGeneratedPattern="Computed" into the model.xml I get this error:

Modifications to tables where a primary key column has property 'StoreGeneratedPattern' set to 'Computed' are not supported. Use 'Identity' pattern instead. Key column: 'act_ActionID'. Table: 'ZillionRIS_developModel.Store.Actions'.

But when I add StoreGeneratedPattern="Identity" into the model.xml I get this error:

Server-generated keys are only supported for identity columns. Key column 'act_ActionID' has type 'SqlServer.uniqueidentifier', which is not a valid type for an identity column.

Am I still missing something?

Re: ASP.NET Dynamic Data + guid

ricka6 — Wed, 27 May 2009 04:21:49 GMT

I agree. I opened a bug some time ago. Note this only occurs in EF, not Linq to SQL. It will be fixed in the next RTM release and probably in the next Beta.

Re: ASP.NET Dynamic Data + guid

suicidesquad — Tue, 26 May 2009 09:51:54 GMT

Thanks,

Now I did the following for EF:

1    <EntityType Name="Actions">
2       <Key>
3          <PropertyRef Name="act_ActionID" />
4       </Key>
5       <Property Name="act_ActionID" Type="uniqueidentifier" Nullable="false" StoreGeneratedPattern="Identity" />
6       <Property Name="act_ActionName" Type="nvarchar" Nullable="false" MaxLength="50" />
7       <Property Name="act_Description" Type="text" />
8    </EntityType>

You see I added the StoreGeneratedPattern="Identity" at line 5, because it is an uniqueidentifier and only needs to be generated at creation.

My assumption was that also the text file would be invisible, but I still get the warning that I have to fill in a value when I try to save the insert. Do I need to add something else?

Re: ASP.NET Dynamic Data + guid

ricka6 — Wed, 20 May 2009 19:01:32 GMT

The solution has alway been to update the XML and let the DB create the GUID.

StoreGeneratedPattern="Computed" // EF
IsDbGenerated="true" // L2S

Re: ASP.NET Dynamic Data + guid

suicidesquad — Wed, 20 May 2009 12:48:34 GMT

Is there a solution for handling the GUID in Preview 4?

Re: ASP.NET Dynamic Data + guid

Gidion — Mon, 11 Aug 2008 19:45:00 GMT

Hi, I have the same problem and came up with the following solution. It changes the dynamic data master template and implements a context menu where you can generate a GUID in the textbox for the primary key. It's a rather lightweight solution (apart from downloading and using jQuery and 2 plugins) that you can implement in a couple of minutes. Maybe someone finds it useful.

Re: ASP.NET Dynamic Data + guid

zwitterion — Tue, 29 Jul 2008 20:50:03 GMT

Too bad. Thanks for the reply though marcind.

Re: ASP.NET Dynamic Data + guid

marcind — Tue, 29 Jul 2008 16:29:31 GMT

Hi zwitterion,

unfortunately there is no better way of doing this as the EF model does not provide Dynamic Data with enough information. A solution will not be available until v2.

Re: ASP.NET Dynamic Data + guid

aspnerd — Tue, 29 Jul 2008 15:25:55 GMT

I would guess there isn't until a new version comes out. It took MS a couple weeks to get back with that solution at this point and I believe they have noted it for the new version.

Re: ASP.NET Dynamic Data + guid

zwitterion — Tue, 29 Jul 2008 15:21:44 GMT

I've been using aspnerd's solution since all my entities have autogenerated (numberic identity) keys and I don't want any of them in my forms. However it seems really wrong to have to break out a partial class every time we want to skip the scaffolding of an autogenerated key which should basically never be scaffolded anyway doesn't it? Is there any better way of doing this?

Re: ASP.NET Dynamic Data + guid

aspnerd — Mon, 02 Jun 2008 20:47:24 GMT

So here is the working solution for this issue.

Using the same namespace as your data model create a class.

Then create your partial class of the table you wish to use a SQL server set newid() guid.

Here is a copy of the class I created.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel.DataAnnotations;

namespace YourOwnDataModel
{     [MetadataType(typeof(ClientInformation_MD))]
     partial class ClientInformation
     {

          public ClientInformation()
          {
               ClientGUID = Guid.NewGuid();
          }

}

     partial class ClientInformation_MD
     {
          [Scaffold(false)]
          public object ClientGUID { get; set; }
     }

}

Re: ASP.NET Dynamic Data + guid

scothu — Thu, 15 May 2008 16:24:18 GMT

Entity Framework does not have the ability to tell Dynamic Data whether a column is generated, so by default we always assume it's not. To work around this, you can put a ScaffoldColumn(false) attribute on the property, e.g.

[MetadataType(typeof(Products_MD))]

partial class Products { }

partial class Products_MD {

[ScaffoldColumn(false)]

public object ProductID { get; set; }

}

Re: ASP.NET Dynamic Data + guid

aspnerd — Thu, 15 May 2008 13:30:38 GMT

were you ever able to get this fixed? I'm having the same issue with Entity Data Model, but I don't see the options they are referring to.