st_grade_manage.aspx.cs

学生管理系统。C#开发。偏重与数据库的应用。

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
public partial class ST_grade_manage : System.Web.UI.Page
{
    SqlConnection st_conn;
    string st_sqlstr;
    protected void Page_Load(object sender, EventArgs e)
    {
        // 在此处放置用户代码以初始化页面
        string st_connstr = ConfigurationManager.AppSettings["st_dbconn"];
        st_conn = new SqlConnection(st_connstr);
    }
    protected void st_btn_exit_Click(object sender, EventArgs e)
    {
        Response.Redirect("default.aspx");
    }
    protected void st_btn_search_Click(object sender, EventArgs e)
    {
        ST_BindGrid();

    }
    public void DataGrid_Page(object sender, DataGridPageChangedEventArgs e)
    {
        st_dtg_grade.CurrentPageIndex = e.NewPageIndex;
        ST_BindGrid();
    }
    public void ST_BindGrid()
    {
        if (st_ddl_way.SelectedItem.Text == "按学号")
        {
            if (st_tbx_term.Text == "所有")
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_student_course.ST_Student_id='" + st_tbx_name.Text + "' and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";
            }
            else
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_student_course.ST_Student_id='" + st_tbx_name.Text + "' and ST_student_course.ST_Course_year='" + st_tbx_term.Text + "' and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";
            }
        }
        else if (st_ddl_way.SelectedItem.Text == "按课号")
        {
            if (st_tbx_term.Text == "所有")
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_student_course.ST_Course_id='" + st_tbx_name.Text + "' and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";
            }
            else
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_student_course.ST_Course_id='" + st_tbx_name.Text + "' and ST_student_course.ST_Course_year='" + st_tbx_term.Text + "' and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";
            }
        }
        else if (st_ddl_way.SelectedItem.Text == "按课程名")
        {
            if (st_tbx_term.Text == "所有")
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_course.ST_Course_name='" + st_tbx_name.Text + "' and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";

            }
            else
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_course.ST_Course_name='" + st_tbx_name.Text + "' and ST_student_course.ST_Course_year='" + st_tbx_term.Text + "' and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";
            }
        }
        else if (st_ddl_way.SelectedItem.Text == "按班级")
        {
            if (st_tbx_term.Text == "所有")
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_student.ST_Student_classid='" + st_tbx_name.Text + "'and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";

            }
            else
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_student.ST_Student_classid='" + st_tbx_name.Text + "' and ST_student_course.ST_Course_year='" + st_tbx_term.Text + "' and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";
            }
        }
        else if (st_ddl_way.SelectedItem.Text == "按教师号")
        {
            if (st_tbx_term.Text == "所有")
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_teacher.ST_Teacher_id='" + st_tbx_name.Text + "' and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";

            }
            else
            {
                st_sqlstr = "select ST_student_course.ST_ID,ST_student_course.ST_Student_id,ST_student.ST_Student_name,ST_student.ST_Student_classid,ST_student_course.ST_Course_id,ST_course.ST_Course_name,ST_teacher.ST_Teacher_name,ST_student_course.ST_Student_grade from ST_course,ST_student,ST_teacher,ST_student_course,ST_teacher_course where ST_teacher.ST_Teacher_id='" + st_tbx_name.Text + "' and ST_student_course.ST_Course_year='" + st_tbx_term.Text + "' and ST_student_course.ST_Course_id=ST_course.ST_Course_id and ST_student_course.ST_Student_id=ST_student.ST_Student_id and ST_student_course.ST_Course_id=ST_teacher_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher_course.ST_Class_id=ST_student.ST_Student_classid";
            }
        }

        SqlCommand st_comm = new SqlCommand(st_sqlstr, st_conn);
        st_conn.Open();
        SqlDataReader dr = st_comm.ExecuteReader();
        if (dr.Read())
        {
            st_dtg_grade.Visible = true;
            st_conn.Close();
            st_conn.Open();
            SqlDataAdapter st_da = new SqlDataAdapter(st_sqlstr, st_conn);
            DataSet st_ds = new DataSet();
            st_da.Fill(st_ds);
            st_dtg_grade.DataSource = st_ds;
            st_dtg_grade.DataBind();
        }
        else
        {
            st_dtg_grade.Visible = false;
            st_lbl_note.Text = "无纪录！";
        }
        st_conn.Close();
    }
    public void DataGrid_cancel(object sender, DataGridCommandEventArgs e)
    {

        st_dtg_grade.EditItemIndex = -1;
        ST_BindGrid();

    }
    public void DataGrid_edit(object sender, DataGridCommandEventArgs e)
    {

        st_dtg_grade.EditItemIndex = (int)e.Item.ItemIndex;
        ST_BindGrid();

    }
    public void DataGrid_update(object sender, DataGridCommandEventArgs e)
    {
        string st_sqlstr = "update ST_student_course set ST_Student_grade=@Student_grade where ST_Student_id=@Student_id and ST_Course_id=@Course_id and ST_ID=@id";
        SqlCommand st_comm = new SqlCommand(st_sqlstr, st_conn);
        st_comm.Parameters.Add(new SqlParameter("@Student_grade", SqlDbType.Int, 4));
        st_comm.Parameters.Add(new SqlParameter("@Course_id", SqlDbType.VarChar, 50));
        st_comm.Parameters.Add(new SqlParameter("@Student_id", SqlDbType.VarChar, 50));
        st_comm.Parameters.Add(new SqlParameter("@id", SqlDbType.Char, 10));
        string st_colvalue = ((TextBox)e.Item.Cells[7].Controls[0]).Text;
        st_comm.Parameters["@Student_grade"].Value = st_colvalue;
        st_comm.Parameters["@Student_id"].Value = e.Item.Cells[1].Text;
        st_comm.Parameters["@Course_id"].Value = e.Item.Cells[4].Text;
        st_comm.Parameters["@Student_grade"].Value = st_colvalue;
        st_comm.Parameters["@id"].Value = st_dtg_grade.DataKeys[(int)e.Item.ItemIndex];
        st_comm.Connection.Open();
        try