Order a list by a property name(string value)?

Answer 1

Order by property name without type reflection

    public static class IQueryableExtensions
    {
      public static IQueryable OrderBy(this IQueryable source, string 
      propertyName)
      {
      return (IQueryable)OrderBy((IQueryable)source, propertyName);
      }

      public static IQueryable OrderBy(this IQueryable source, string propertyName)
      {
        var x = Expression.Parameter(source.ElementType, "x");
        var body = propertyName.Split('.').Aggregate(x, 
        Expression.PropertyOrField);

        var selector = Expression.Lambda
         (Expression.PropertyOrField(x, propertyName), x);

         return source.Provider.CreateQuery(
            Expression.Call(typeof(Queryable), "OrderBy", new Type[] { 
             source.ElementType, selector.Body.Type },
                 source.Expression, selector
                 ));
      }

      public static IQueryable OrderByDescending(this IQueryable source, 
      string propertyName)
      {
        return (IQueryable)OrderByDescending((IQueryable)source, propertyName);
      }

      public static IQueryable OrderByDescending(this IQueryable source, string 
      propertyName)
      {
        var x = Expression.Parameter(source.ElementType, "x");
        var selector = Expression.Lambda(Expression.PropertyOrField(x, 
        propertyName),x);
        return source.Provider.CreateQuery(
            Expression.Call(typeof(Queryable), "OrderByDescending", new Type[] { 
             source.ElementType, selector.Body.Type },
                 source.Expression, selector
                 ));
      }
}