var returnall = from p in db.Orders
                orderby p.ShipName
                select p.ShipName;

各种LINQ函数的方便参考可在MSDN samples page上找到。

您可以使用OrderBy对多个属性的单个属性进行排序，还可以使用ThenBy

DataClasses1DataContext db = new DataClasses1DataContext();
 var returnall = db.OrderBy(r=> r.OrderDelivaryDate).
                    ThenBy(r => r. OrderName);

此查询将首先按OrderDelivaryDate排序，然后按OrderName排序
下面是一些简单的linq查询http://msdn.microsoft.com/en-us/vcsharp/aa336756#thenBySimple

var ret = db.Orders.OrderBy( x => x.ShipName );

order by

要对一个或多个字段的查询结果进行排序，请执行以下操作：

数据：

List<Employee> emp = new List<Employee>() { new Employee() { emp_id = 101, emp_name = "David", emp_lang = "Java", dpt_id = 1 }
                                                    ,new Employee() { emp_id = 102, emp_name = "Lana",emp_lang = "C#", dpt_id = 2 }
                                                    ,new Employee() { emp_id = 103, emp_name = "Sona",emp_lang = "Java", dpt_id = 3 }
                                                    ,new Employee() { emp_id = 104, emp_name = "Mike",emp_lang = "C++", dpt_id = 3 }
                                                    ,new Employee() { emp_id = 105, emp_name = "Roma",emp_lang = "C#", dpt_id = 1 }

查询：

var res = from e in emp
              orderby e.emp_lang, e.dpt_id
              select new { e.emp_name, e.emp_lang, e.dpt_id }

结果：

{ emp_name = "Roma", emp_lang = "C#", dpt_id = 1 }
{ emp_name = "Lana", emp_lang = "C#", dpt_id = 2 }
{ emp_name = "Mike", emp_lang = "C++", dpt_id = 3 }
{ emp_name = "David", emp_lang = "Java", dpt_id = 1 }
{ emp_name = "Sona", emp_lang = "Java", dpt_id = 3 }