LINQ To SQL在N层应用程序中的CUD操作、批量删除、批量更新

   6:  

   7: UpdateBatch(predicate, evaluator);  //批量更新

   8: DeleteBatch(predicate);  //批量删除

   9: MultiSelect();           //批量查询

  10: DeleteByPK(productID);   //按主键删除

  11:  

  12: public void UpdateBatch(Expression<Func<Products, bool>> predicate,

  13:     Expression<Func<Products, Products>> evaluator)

  14: {

  15:     using (NorthWindDataContext context = new NorthWindDataContext())

  16:     {

  17:         context.Products.UpdateBatch(predicate, evaluator);

  18:     }

  19: }

  20:  

  21: public void DeleteBatch(Expression<Func<Products, bool>> predicate)

  22: {

  23:     using (NorthWindDataContext context = new NorthWindDataContext())

  24:     {

  25:         context.Products.DeleteBatch(predicate);

  26:     }

  27: }

  28:  

  29: public void MultiSelect()

  30: {

  31:     using (NorthWindDataContext context = new NorthWindDataContext())

  32:     {

  33:         var query1 = (from P in context.Products select P).Take(2);

  34:         var query2 = (from S in context.Suppliers select S).Take(2);

  35:         IMultipleResults result = context.SelectMutlipleResults(query1, query2);

  36:  

  37:         List<Products> products = result.GetResult<Products>().ToList();

  38:         List<Suppliers> suppliers = result.GetResult<Suppliers>().ToList();

  39:         ObjectDumper.Write(products);

  40:         ObjectDumper.Write(suppliers);

  41:     }

  42: }

  43:  

  44: public void DeleteByPK(int productID)

  45: {

  46:     using (NorthWindDataContext context = new NorthWindDataContext())

  47:     {

  48:         context.Products.DeleteByPK(productID);

  49:     }

  50: }