How to lazy-load a single property on a Linq entity?

Question

I'm hand-coding Linq to SQL Entities and have a large XML column that I don't want loaded each time this entity is loaded, as it's infrequently used. Everywhere I search, I see that the Linq to SQL designer provides a "Delay Loaded" property, but the ColumnAttribute class doesn't have any hints as to how this is implemented.

I've gathered it's related to the System.Data.Linq.Link class, but I haven't found the magic incantation to make it work.

Does anyone know how to implement a lazy-loaded property in a hand-coded Linq to SQL C# class?

Answer 1

I've dissected the results of the designer's generated code.

Step 1: Create a private member using the System.Data.Linq.Link type:

private System.Data.Linq.Link<String> _columnName;

Step 2: Set the Storage parameter of the Column attribute to this member name, and fill in the property getter and setters:

[Column(Name = "column_name", Storage = "_columnName"...]
public String ColumnName 
{
    get
    {
        return _columnName.Value;
    }
    set
    {
        _columnName.Value = value;
    }
}