Linq ToList出错

Linq ToList出错：

public IList <adr_GaCha> GaChas()
  {
  IList <adr_GaCha> adr_gaCha = new List <adr_GaCha>();
  var query = from c in dc.adr_GaChas select new { c.adr_GaCha_ID, c.adr_GaCha_Name };
  adr_gaCha = query.ToList();//出错行
  return adr_gaCha;
 
 
  }

------解决方法--------------------------------------------------------

C# code

public IList  GaChas()         {             IList  adr_gaCha = new List ();             var query = from c in dc.adr_GaChas select new adr_GaCha {adr_GaCha_ID = c.adr_GaCha_ID, adr_GaCha_Name = c.adr_GaCha_Name };             adr_gaCha = query.ToList();            return adr_gaCha;                  }

C# code

public IList <adr_GaCha> GaChas()         {             IList <adr_GaCha> adr_gaCha = new List <adr_GaCha>();             var query = from c in dc.adr_GaChas select c;             adr_gaCha = query.ToList();//出错行             return adr_gaCha;         }