Question

I have the following extension method, and would like to make it more generic so I don’t have to implement it for every class in our domain.

public static IList<User> ToList(this DataTable table) {     IList<User> users = new List<User>();      foreach (DataRow row in table.Rows)         users.Add(User.FromDataRow(row));      return users; } 

Is there any way to work around this frustrating limitation?

edit: the below paragraph is bollocks, but I’m keeping it so one of the answers makes sense to future readers:

User, as well as my other classes, implements IDataModel. IDataModel only requires 1 method, FromDataRow(DataRow row). Putting a where into the function prototype obviously doesn’t help.

Answer 1

When you only need one method, think Func… perhaps a Func<DataRow, T>

public static IList<T> ToList<T>(this DataTable table,       Func<DataRow,T> converter) {     IList<T> list = new List<T>();      foreach (DataRow row in table.Rows)         list.Add(converter(row));      return list; } 

Then call table.ToList<User>(User.FromDataRow)