Sort a List using query expressions

Question

I have a problem using Linq to order a structure like this :

public class Person
{
    public int ID { get; set; }
    public List Attribu         


        

Answer 1

I know this is an old post, but I thought I'd post a comparer I found a while ago in case anyone else needs it.

public class GenericComparer : IComparer
 {
     public string SortExpression { get; set; }
     public int SortDirection { get; set; } // 0:Ascending, 1:Descending

     public GenericComparer(string sortExpression, int sortDirection)
     {
         this.SortExpression = sortExpression;
         this.SortDirection = sortDirection;
     }
     public GenericComparer() { }

     #region IComparer Members
     public int Compare(T x, T y)
     {
         PropertyInfo propertyInfo = typeof(T).GetProperty(SortExpression);
         IComparable obj1 = (IComparable)propertyInfo.GetValue(x, null);
         IComparable obj2 = (IComparable)propertyInfo.GetValue(y, null);

         if (SortDirection == 0)
         {
             return obj1.CompareTo(obj2);
         }
         else return obj2.CompareTo(obj1);
     }
     #endregion
 }

Usage

List objectList = GetObjects(); /* from your repository or whatever */
objectList.Sort(new GenericComparer("ObjectPropertyName", (int)SortDirection.Descending));
dropdown.DataSource = objectList;
dropdown.DataBind();

You could overload the constructor to accept the SortDirection enum. I didn't do this because the class is in a library without a reference to System.Web.