DeleteObject方法不会删除任何内容 - 请帮忙。(DeleteObject method doesn't delete anything - please help.)

   IT问题网   2021-03-12 00:00:00

问 题

您好。我正在尝试创建将从数据库中删除行的方法。

但是由于某些原因,当我启动程序时,没有任何删除,也没有错误弹出。

我做错了什么与db.orders.deleteobject(ordertodelete);?







 console.writeline(" 请输入您要删除的订单id"); 
尝试
{
int choice3 = int .parse(到console.readline());
var ordertodelete =( from c in db.orders
其中 c.orderid == choice3
选择 c).firstordefault();

if (ordertodelete!= null
{
db.orders.deleteobject(ordertodelete);
}
var orderexists =( from c in db.orders
其中 c.orderid == choice3
选择 c).firstordefault();
if (orderexists!= null
{
console。 writeline(" 订单未删除。");
deletefromdatabase();
}
else
{
console.writeline(" 订单已删除。");
mainmenu();
}
}

解决方案

您不能保存(提交)更改,以确保它们是没有保存。如果你已经阅读过这些文档,你就会知道文档中有示例代码: objectcontext.deleteobject[ ^ ]



顺便说一下,谷歌很容易找到答案。

非常感谢。我是笨蛋。 :)

标签:方法法子不会删除任何内容帮忙



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