protected void Button5_Click(object sender, EventArgs e)
{
Model2Container db = new Model2Container();
//方式1
//var customer = (from c in db.Customer
// where c.Id == 1
// select c).FirstOrDefault();
//var orderInfoList = customer.OrderInfo;
////遍历所有
//while (orderInfoList.Count > 0)
//{
// var orderInfo = orderInfoList.FirstOrDefault();
// db.Entry(orderInfo).State = System.Data.Entity.EntityState.Deleted;
//}
//db.SaveChanges();
var orderList = from o in db.OrderInfo
where o.CustomerId == 4
select o;
foreach (var item in orderList)
{
db.Entry(item).State = System.Data.Entity.EntityState.Deleted;
}
db.SaveChanges();
}
protected void Button4_Click(object sender, EventArgs e)
{
Model2Container db = new Model2Container();
var orderInfoList = from c in db.OrderInfo
where c.OrderNum == "10001"
select c;
var orderInfo = orderInfoList.FirstOrDefault();
Response.Write(orderInfo.Customer.CustomerName);
}
protected void Button2_Click(object sender, EventArgs e)
{
//导航属性应用
Model2Container db = new Model2Container();
var customerList = from c in db.Customer
select c;
foreach (var item in customerList)
{
//打印名字及他用户下的订单号
Response.Write(item.CustomerName + ":");
foreach (var orderInfo in item.OrderInfo)
{
Response.Write(orderInfo.OrderNum);
}
}
}
protected void Button1_Click(object sender, EventArgs e)
{
Model2Container db = new Model2Container();
Customer customer = new Customer()
{
CustomerName = "张三", CustomerPwd = "123", SubTime = DateTime.Now
};
OrderInfo orderInfo1 = new OrderInfo()
{
Id = Guid.NewGuid(), OrderNum = "10001", CreateDateTime = DateTime.Now, Customer = customer
};
OrderInfo orderInfo2 = new OrderInfo()
{
Id = Guid.NewGuid(), OrderNum = "10002", CreateDateTime = DateTime.Now, Customer = customer
};
db.Customer.Add(customer);
db.OrderInfo.Add(orderInfo1);
db.OrderInfo.Add(orderInfo2);
db.SaveChanges();
}
protected void Button3_Click(object sender, EventArgs e)
{
Model2Container db = new Model2Container();
//常规方式
//var customerInfoList = from c in db.Customer
// where c.Id == 1
// select c;
//var customerInfo = customerInfoList.FirstOrDefault();
//foreach (var item in customerInfo.OrderInfo)
//{
// Response.Write(customerInfo.CustomerName + ":" + item.OrderNum + "\r\n");
//}
//简化方式
var orderInfoList = from c in db.OrderInfo
where c.CustomerId == 1
select c;
foreach (var item in orderInfoList)
{
Response.Write(item.OrderNum);
}
}