Owin Framework

The [IsDataProvider] Attribute

Attach this attribute to a class to identify it as a data provider.

Example Usage

[IsDataProvider("customer", typeof(Customer))]
internal class CustomerDataProvider : DataProvider
{
    public CustomerDataProvider(IDataProviderDependenciesFactory dependencies) 
        : base(dependencies)
    {
    }
    protected override void Supply(
        IRenderContext renderContext,
        IDataContext dataContext,
        IDataDependency dependency)
    {
        dataContext.Set(new Customer());
    }
}

The [IsDataProvider()] attribute has the following properties you can set.

Name

You can explicitly name your data providers and define data dependencies using these names, however this is not the most common use case because specifying data needs in terms of the type of data is much more powerful and flexible.

Even if you are not using the name of the data provider to define data needs, it's still a good idea to set it because it will make diagnostic traces and debug information more meaningful.

Type

Defines the type of data that this data provider can provide. This must be either a C# class type, or an IList<T> type.

Scope

Specifies a scope name. When this is set, this data provider will only be considered as the supplier of data when the page element specifies that it needs data in this specific scope.

When the scope name is not set, this means that this data provider can provide this kind of data for all scopes. In this case this data provider will only be used if there are no scope specific data providers that match the request.

In the case where there are multiple data providers that can provide the data, the one that will be selected depends on what other data is required on the page, and the other types of data that each provider can provide.