C#------对SQLServer进行简单的增，删，改，查

EF中的操作
转载：

http://www.cnblogs.com/mcgrady/archive/2015/03/21/4355282.html

PSContext db = new PSContext();

//遍历所有数据，根据id排序（查）
var time = db.Timetables.AsNoTracking().OrderBy(p => p.id).ToList();
foreach (var t in time)
{
　　Console.WriteLine("{0},{1}",t.id,t.time);
}

//遍历所有数据，根据ID倒序排序（查）
var student = db.Students.AsNoTracking().OrderByDescending(p => p.ID).ToList();
foreach (var s in student)
{
　　Console.WriteLine("{0},{1}", s.ID, s.Name);
}

//从ID为5的数据开始，往后遍历4个数据（查）
var student = db.Students.OrderBy(p => p.ID).Where(p => p.ID > 4).Skip(4).Take(4).ToList();
foreach (var s in student)
{
　　Console.WriteLine("{0},{1}", s.ID, s.Name);
}

//往数据库添加数据（增）
var teacher = new Teacher();
teacher.ID = 2432;
teacher.Name = "绿豆";
db.Teachers.Add(teacher);
db.SaveChanges();

//对Name为qwe的项进行修改（改）
var teacher = db.Teachers.Single(u => u.Name == "菠萝");
teacher.Name = "苹果";
db.SaveChanges();

//对指定列进行删除（删）
Student student = db.Students.Find(5);
Console.WriteLine("{0},{1}",student.ID,student.Name);
db.Students.Attach(student);
db.Students.Remove(student);
db.SaveChanges();