asp.net - IList or IQueryable OrderBy method which accepts a string parameter as selector? -

this asp.net entity framework tutorial describes how can use objectdatasource bll , provide method includes sort expression use gridview.

public ienumerable<department> getdepartments(string sortexpression) {     if (string.isnullorwhitespace(sortexpression))     {         sortexpression = "name";     }              return context.departments.include("person").orderby("it." + sortexpression).tolist(); } 

the problem is, uses string sortexpression objectdatasource in orderby() method. can't find reference method anywhere. exist , if not, best way allow sorting of gridview custom bll.

dynamic linq supports orderby string argument: http://dynamiclinq.codeplex.com/