Data Access Continued: Crud Parameter Attribute

In my last blog entry, I decided to pursue writing a data access component model. I have further defined some more requirements:

• Classes of type T will be required to decorate their properties that are going to be considered as parameters within the ICrud<T> data access implementation. 
• When applying this decorating attribute to a property, you will be required to provide the following values:
• ParameterDirection: this will denote if the parameter should expect a value back after the CRUD operation was successful.
• (Optional) ParameterName: the text used by the ICrud<T> implementation if the CRUD operation needs a different name for the value other than what the parameters base name.

That's enough about requirements! Below is the implementation of this definition!:

[AttributeUsage(AttributeTargets.Property, AllowMultiple=false, Inherited=true)]

public class CrudParameterAttribute:Attribute

{

    public const string NO_PARAMETER_NAME = "NoParameterName";

    /// <summary>

    /// defines what the Crud data access will interpret the property. 

    /// </summary>

    /// <remarks>

    /// regardless of the direction assigned, the read operations will 

    /// attempt to populate the property. Read operations will only 

    /// use parameters passed into the ICrud object via the 

    /// AddParameter method call.

    /// </remarks>

    public enum Direction 

    {

        /// <summary>

        /// Defines that the property will not be updated by the 

        /// ICrud object after a Create, Update, or Delete calls

        /// </summary>

        Input,

        /// <summary>

        /// Defines that the value within the decorated property

        /// can be effectively ignored for the Create, Update, 

        /// or Delete calls, but it will be populated when the

        /// operation is completed.

        /// </summary>

        Output,

        /// <summary>

        /// Defines that the parameter can be used by the ICrud object

        /// for supplying values, and will be updated after the Create,

        /// Update, or Delete operation is completed.

        /// </summary>

        Both

    }

    /// <summary>

    /// The name that the ICrud operation will used to identify the 

    /// property value uniquely

    /// </summary>

    public string ParameterName { get; private set; }

    /// <summary>

    /// Our way to effect how the ICrud implementation will 

    /// interpret this property

    /// </summary>

    public Direction ParameterDirection { get; private set; }

    /// <summary>

    /// Defines how this property will be interpreted as a parameter 

    /// within an ICrud implementation

    /// </summary>

    /// <param name="direction">

    /// If the property will be populated after an Update, Create, 

    /// or Delete

    /// </param>

    public CrudParameterAttribute(Direction direction)

    {

        this.ParameterDirection = direction;

        // denotes that the property name should be used

        this.ParameterName = NO_PARAMETER_NAME; 

    }

    /// <summary>

    /// Defines how this property will be interpreted as a parameter 

    /// within an ICrud implementation

    /// </summary>

    /// <param name="direction">

    /// If the property will be populated after an Update, Create,

    /// or Delete

    /// </param>

    /// <param name="parameterName">

    /// If the ICrud implementation should refer to the parameter 

    /// by another other than the properties existing name.

    /// </param>

    public CrudParameterAttribute(Direction direction, 

                                   string parameterName)

    {

        this.ParameterDirection = direction;

        this.ParameterName = ParameterName;

    }

}