写student类中的select，delete，update，insert方法并在objectDataSource中应用（分别写两个，一个返回datatable，一个使用list）

public DataTable StudentsSelect()

{

string sql = "select sid,sname,sex,age,photo from student";

return sqlHealpler.sqlHealper.ExecuteTable(sql);

}

public int StudentDelete(int sid)

{

string sql = "delete from student where sid=@id";

SqlParameter pms=new SqlParameter("@id",sid);

return sqlHealpler.sqlHealper.ExecturNonQuery(sql,pms);

}
public int StudentInsert(int sid, string sname, string sex, int age, string photo)

{

string sql = "insert into student values(@sname,@sex,@age,@photo)";

SqlParameter[] pms = new SqlParameter[]

{

new SqlParameter("@sname",sname),

new SqlParameter("@sex",sex),

new SqlParameter("@age",age),

new SqlParameter("@photo",photo),

//new SqlParameter("@id",sid)

};

return sqlHealpler.sqlHealper.ExecturNonQuery(sql, pms);

}

public int StudentUpdate(int sid,string sname,string sex,int age,string photo)

{

string sql = "Update student set
sname=@sname,sex=@sex,age=@age,photo=@photo where sid=@id";

SqlParameter[] pms = new SqlParameter[]

{

new SqlParameter("@sname",sname),

new SqlParameter("@sex",sex),

new SqlParameter("@age",age),

new SqlParameter("@photo",photo),

new SqlParameter("@id",sid)

};

return sqlHealpler.sqlHealper.ExecturNonQuery(sql, pms);

}

返回list

public int sid { get; set; }

public string sname { get; set; }

public string sex { get; set; }

public int age { get; set; }

public string photo { get; set; }

public List<Student> GetStudents()

{

string sql = "select sid,sname,sex,age,photo from student";

DataTable dt = sqlHealpler.sqlHealper.ExecuteTable(sql);

List<Student> list = new List<Student>();

foreach (DataRow row in dt.Rows)

{

Student stu = new Student();

stu.sid = (int)row[0];

stu.sname = row[1].ToString();

stu.sex = row[2].ToString();

stu.age = Convert.ToInt32(row[3]);

stu.photo = row[4].ToString();

list.Add(stu);

}

return list;

}