Is there any way to add custom attributes to properties in EF generated code? The only thing I can see as a plausible solution would be to come up with a custom T4 template. However, because of the nature of the attribute it would be impossible to determine the correct attribute parameter per EF property.
You can do this by specifying a metadata type that mirrors the properties and is used simply for attribution.
[MetadataType(typeof(Dinner_Validation))]
public partial class Dinner
{}
public class Dinner_Validation
{
[Required]
public string Title { get; set; }
}
Steve Smith blogs about it here.
Unfortunately the above approach is brittle to refactoring. Another option is to use the new POCO entities. These avoid compile-time code generation altogether as far as I can tell. I haven't used them yet so can't comment on any pitfalls or tradeoffs.
You can add this to EDMX file, with Designer also:
<Property Name="Nome" Type="String" Nullable="false" MaxLength="50" Unicode="true" FixedLength="false" >
<Documentation>
<Summary>[MyCustomAttribute]</Summary>
</Documentation>
</Property>
And replace T4:
void WriteProperty(CodeGenerationTools code, EdmProperty edmProperty)
{
WriteProperty(Accessibility.ForProperty(edmProperty),
code.Escape(edmProperty.TypeUsage),
code.Escape(edmProperty),
code.SpaceAfter(Accessibility.ForGetter(edmProperty)),
code.SpaceAfter(Accessibility.ForSetter(edmProperty)));
}
With:
void WriteProperty(CodeGenerationTools code, EdmProperty edmProperty)
{
if(edmProperty.Documentation != null && string.IsNullOrWhiteSpace(edmProperty.Documentation.Summary) == false)
{
#>
<#=edmProperty.Documentation.Summary#>
<#+
}
WriteProperty(Accessibility.ForProperty(edmProperty),
code.Escape(edmProperty.TypeUsage),
code.Escape(edmProperty),
code.SpaceAfter(Accessibility.ForGetter(edmProperty)),
code.SpaceAfter(Accessibility.ForSetter(edmProperty)));
}