/// <summary>
/// （增）向表中插入数据
/// </summary>
public void InsertData()
{
LinqToSQLDataContext dataContent = new LinqToSQLDataContext();
//InsertOnSubmit(TEntity entity)方法向表一次插入一条记录
employee e = new employee() { id = 4, name = "sujina", age = 22, position = "教师", partment = "狮子场小学" };
dataContent.employee.InsertOnSubmit(e);
//InsertAllOnSubmit<TSubEntity>(IEnumerable<TSubEntity> entities) 向表中一次插入多条记录
employee e1 = new employee() { id = 5, name = "sujina", age = 22, position = "教师", partment = "狮子场小学" };
employee e2 = new employee() { id = 6, name = "sujina", age = 22, position = "教师", partment = "狮子场小学" };
List<employee> epList = new List<employee>() { e1, e2 };
dataContent.employee.InsertAllOnSubmit(epList);
dataContent.SubmitChanges();//计算要插入、更新或删除的已修改对象的集，并执行相应的命令以实现对数据库的更改
}
/// <summary>
/// （删）删除数据
/// </summary>
public void deleteData()
{
LinqToSQLDataContext dataContent = new LinqToSQLDataContext();
//删除一个实体
//Single<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)返回序列中满足指定条件的唯一元素；如果有多个这样的元素存在则会报错
employee deletes = dataContent.employee.Single(x => x.id == 4);
dataContent.employee.DeleteOnSubmit(deletes);
//删除多个实体
IEnumerable<employee> delete = dataContent.employee.Where(x => x.id == 2).Select(x => x);//兰姆达表达式
//IEnumerable<employee> delete = from s in dataContent.employee where s.id == 2 select s;//linq写法
dataContent.employee.DeleteAllOnSubmit(delete);
dataContent.SubmitChanges();
}
/// <summary>
/// （改）更新数据
/// </summary>
public void updteData()
{
LinqToSQLDataContext dataContent = new LinqToSQLDataContext();
//查出多条数据
IEnumerable<employee> update = dataContent.employee.Where(x => x.id > 4).Select(x => x);//IEnumerable<employee>类型
//IEnumerable<employee> update = from s in dataContent.employee where s.id >4 select s;//IEnumerable<employee>类型
foreach (var item in update)
{
item.name = "zybsjn";
item.partment = "酒店学校";
item.position = "教师程序员";
}
//查出单条数据
employee ep = dataContent.employee.Single(x => x.id == 5);
ep.name = "小娜娜";
dataContent.SubmitChanges();
}