教师管理操作流程1、使用 Teacher 账号登陆——教师管理系统代码区域：if (loginType == "教师") { string sql = string.Format("select count(*) from teacher where LoginId='{0}' AND LoginPwd='{1}'", loginId, loginPwd); try { SqlCommand command = new SqlCommand(sql, DBHelper.connection); DBHelper.connection.Open(); count = (int)command.ExecuteScalar(); if (count == 1) { isValidUser = true; } else { index++; if (index <= 3) { message = "用户名或密码不存在！"; } else if (index >= 3) { Application.Exit(); } isValidUser = false; } } catch (Exception ex) { message = ex.Message; Console.WriteLine(ex.Message); }查询修改信息查询教师基本信息(代码区域：) TeacherBaseForm teacherBaseForm = new TeacherBaseForm(); teacherBaseForm.Show();TeacherBaseForm（教师基本信息窗体）查询及修改学生信息(代码区域：) UpdateStudentForm updateStudentForm = new UpdateStudentForm(); updateStudentForm.Show();SearchTeacherForm.cs（查询及修改信息窗体）AddScoreForm（学生成绩录入窗体）录入按钮代码：string sql = string.Format("select StudentId,StudentNo,StudentName from Student where StudentId='{0}'", txtId.Text); try { SqlCommand command = new SqlCommand(sql, DBHelper.connection); DBHelper.connection.Open(); SqlDataReader reader = command.ExecuteReader(); while (reader.Read()) { id = (int)reader["StudentId"]; no = (string)reader["StudentNo"]; name = (string)reader["StudentName"]; } reader.Close(); } catch (Exception ex) { MessageBox.Show(ex.Message); } finally { DBHelper.connection.Close(); } if (TianJia()) { if (txtId.Text == Convert.ToString(id) && txtStudentNo.Text == no && txtStudentName.Text == name) { string studentName = txtStudentName.Text; string sdudentNo = txtStudentNo.Text; string subject = cboSubject.Text; string score = txtScore.Text; int classId = GetClassId(); string studentId = txtId.Text; string sql1 = string.Format("i...
