LINQ管理sql server数据库(增删改)
添加数据
DataClasses1DataContext datacontent;
string str = ConfigurationManager.AppSettings["SQLString"].ToString();datacontent = new DataClasses1DataContext(str); //实例化LINQ连接对象
Message message = new Message(); //实例化Message类对象
message.Mess_Title = "new message";
message.Mess_Content = "message content";
datacontent.Message.InsertOnSubmit(message); //将处于pending insert 状态的实体添加到sql数据表中,
datacontent.SubmitChanges(); // 记录要插入,更新或删除的对象,并执行相应的命令以实现对数据库的更改如果想实现使用数据库设置的默认值,那么就要修改LinqToSql文件相对应的列的属性 IsDbGenerated = true
修改数据
DataClasses1DataContext datacontent;
string str = ConfigurationManager.AppSettings["SQLString"].ToString();//查出要修改的实体
datacontent = new DataClasses1DataContext(str);
var data = from msg in datacontent.Message where msg.Mess_ID.ToString() == "7CE24F78-9B3C-44AD-B00B-908F3EA5C44D" select msg;//给实体赋予新的值
foreach (Message item in data)
{
item.Mess_Title = "11";
datacontent.SubmitChanges(); //提价修改,并修改数据库}
删除数据
DataClasses1DataContext datacontent;
string str = ConfigurationManager.AppSettings["SQLString"].ToString();//查出要删除的实体
datacontent = new DataClasses1DataContext(str);
var data = from msg in datacontent.Message where msg.Mess_ID.ToString() == "7CE24F78-9B3C-44AD-B00B-908F3EA5C44D" select msg;
IEnumerable<Message> m = data;
datacontent.Message.DeleteAllOnSubmit(m);
datacontent.SubmitChanges();