任课修改删除.aspx.cs

学生管理系统 功能不是很强大 但是很实用

using System;
using System.Data;
using System.Data.SqlClient;
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;

public partial class 任课信息修改 : System.Web.UI.Page
{
    public SqlDataAdapter myadapter;
    SqlConnection mysqlconnection;
    DataSet myDataSet;
    SqlCommand mysqlcommand;
    public void load()
    {
        String sqlconn = "data source=.;database=学生成绩智能管理系统;user id=sa;password=sa;";
        mysqlconnection = new SqlConnection(sqlconn);
        mysqlcommand = mysqlconnection.CreateCommand();
        mysqlcommand.CommandText = "select distinct 成绩表.课程名,课程表.课程号 from 成绩表,学生表,课程表,教师表 where 成绩表.课程号=课程表.课程号 and 成绩表.学号=学生表.学号 and 成绩表.任课教师编号=教师表.教师编号 order by 课程表.课程号";
        mysqlconnection.Open();
        SqlDataReader myDataReader = mysqlcommand.ExecuteReader();
            DropDownList1.Items.Clear();
            while (myDataReader.Read())
            {
                this.DropDownList1.Items.Add(myDataReader.GetValue(0).ToString());
            }

            myDataReader.Close();
        mysqlconnection.Close();
        mysqlconnection.Open();
            mysqlcommand = mysqlconnection.CreateCommand();
            mysqlcommand.CommandText = "select distinct 成绩表.课程号 from 成绩表,课程表 where 课程表.课程号=(select min(课程号) from 课程表 ) and 成绩表.课程号=课程表.课程号";
            myDataReader = mysqlcommand.ExecuteReader();
            while (myDataReader.Read())
            {
                this.DropDownList3.Items.Add(myDataReader.GetValue(0).ToString());
            }
            myDataReader.Close();
        mysqlconnection.Close();
        mysqlconnection.Open();
        mysqlcommand.CommandText = "select distinct 成绩表.日期 as 日期 from 成绩表,课程表 where 课程表.课程号=(select min(课程号) from 课程表 ) and 成绩表.课程号=课程表.课程号";
            myDataReader = mysqlcommand.ExecuteReader();
            while (myDataReader.Read())
            {
                this.DropDownList2.Items.Add(myDataReader.GetValue(0).ToString());
            }
            myDataReader.Close();
        mysqlconnection.Close();
        mysqlconnection.Open();
            mysqlcommand.CommandText = "select distinct 教师编号 from 教师表";
            myDataReader = mysqlcommand.ExecuteReader();
            while (myDataReader.Read())
            {
                this.DropDownList4.Items.Add(myDataReader.GetValue(0).ToString());
            }
        mysqlconnection.Close();
    }
    protected void Page_Load(object sender, EventArgs e)
    {
        String sqlconn = "data source=.;database=学生成绩智能管理系统;user id=sa;password=sa;";
        mysqlconnection = new SqlConnection(sqlconn);
        mysqlcommand = mysqlconnection.CreateCommand();
        mysqlcommand.CommandText = "select distinct 课程表.课程名,课程表.课程号 from 成绩表,学生表,课程表,教师表 where 成绩表.课程号=课程表.课程号 and 成绩表.学号=学生表.学号 and 成绩表.任课教师编号=教师表.教师编号 order by 课程表.课程号";
        mysqlconnection.Open();
        SqlDataReader myDataReader = mysqlcommand.ExecuteReader();
        if (!IsPostBack)
        {
            while (myDataReader.Read())
            {
                this.DropDownList1.Items.Add(myDataReader.GetValue(0).ToString());
            }

            myDataReader.Close();
        }
        mysqlconnection.Close();
        mysqlconnection.Open();
        if (!IsPostBack)
        {
            mysqlcommand = mysqlconnection.CreateCommand();
            mysqlcommand.CommandText = "select distinct 成绩表.课程号 from 成绩表,课程表 where 课程表.课程名='高等数学' and 成绩表.课程号=课程表.课程号";
            myDataReader = mysqlcommand.ExecuteReader();
            while (myDataReader.Read())
            {
                this.DropDownList3.Items.Add(myDataReader.GetValue(0).ToString());
            }
            myDataReader.Close();
        }
        mysqlconnection.Close();
        mysqlconnection.Open();
        if (!IsPostBack)
        {
            mysqlcommand.CommandText = "select distinct 成绩表.日期 as 日期 from 成绩表,课程表 where 课程表.课程名='高等数学' and 成绩表.课程号=课程表.课程号";
            myDataReader = mysqlcommand.ExecuteReader();
            while (myDataReader.Read())
            {
                this.DropDownList2.Items.Add(myDataReader.GetValue(0).ToString());
            }
            myDataReader.Close();
        }
        mysqlconnection.Close();
        mysqlconnection.Open();
        if (!IsPostBack)
        {
            mysqlcommand.CommandText = "select distinct 教师编号 from 教师表";
            myDataReader = mysqlcommand.ExecuteReader();
            while (myDataReader.Read())
            {
                this.DropDownList4.Items.Add(myDataReader.GetValue(0).ToString());
            }
        }
        mysqlconnection.Close();
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        mysqlcommand = mysqlconnection.CreateCommand();
        mysqlcommand.CommandText = "select distinct 课程表.课程号,课程表.课程名,教师表.教师编号,教师表.姓名,成绩表.日期 from 成绩表,学生表,课程表,教师表 where 成绩表.课程号=课程表.课程号 and 成绩表.学号=学生表.学号 and 成绩表.任课教师编号=教师表.教师编号 and 课程表.课程号= '" + DropDownList3.Text + "' and 成绩表.日期= '" + DropDownList2.Text + "'";
        mysqlconnection.Open();
        SqlDataReader myDataReader = mysqlcommand.ExecuteReader();
        if (myDataReader.Read())
        {
            TextBox2.Text = myDataReader.GetValue(0).ToString();
            TextBox3.Text = myDataReader.GetValue(1).ToString();
            DropDownList4.Text = myDataReader.GetValue(2).ToString();
            TextBox5.Text = myDataReader.GetValue(3).ToString();
            TextBox6.Text = myDataReader.GetValue(4).ToString();
        }
    }
    protected void Button2_Click(object sender, EventArgs e)
    {
        mysqlcommand = mysqlconnection.CreateCommand();
        mysqlconnection.Open();
        mysqlcommand.CommandText = "update 成绩表 set 任课教师编号=" + "'" + DropDownList4.Text + "'" + " where 成绩表.课程号='" + TextBox2.Text + "' and 成绩表.日期='" + TextBox6.Text + "'";
        int returnValue = (int)mysqlcommand.ExecuteNonQuery();
        if (returnValue != 0)
        {
            Response.Write("<script>alert('修改成功!');</script>");
        }
        else
            Response.Write("<script>alert('未知错误!');</script>");
    }
    protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
    {
        mysqlcommand = mysqlconnection.CreateCommand();
        mysqlconnection.Open();
        mysqlcommand.CommandText = "select distinct 成绩表.课程号 from 成绩表,课程表 where 成绩表.课程号=课程表.课程号 and 课程表.课程名='" + DropDownList1.Text + "'";
        SqlDataReader myDataReader = mysqlcommand.ExecuteReader();
        DropDownList3.Items.Clear();
        while (myDataReader.Read())
        {
            this.DropDownList3.Items.Add(myDataReader.GetValue(0).ToString());
        }
        myDataReader.Close();
        mysqlconnection.Close();
        mysqlconnection.Open();
        mysqlcommand.CommandText = "select distinct 成绩表.日期 as 日期 from 成绩表,课程表 where 成绩表.课程号=课程表.课程号 and 课程表.课程名='" + DropDownList1.Text + "'";
        myDataReader = mysqlcommand.ExecuteReader();
        DropDownList2.Items.Clear();
        while (myDataReader.Read())
        {
            this.DropDownList2.Items.Add(myDataReader.GetValue(0).ToString());
        }
        myDataReader.Close();
        mysqlconnection.Close();
    }
    protected void DropDownList4_SelectedIndexChanged(object sender, EventArgs e)
    {
        mysqlcommand = mysqlconnection.CreateCommand();
        mysqlconnection.Open();
        mysqlcommand.CommandText = "select 姓名 from 教师表 where 教师编号='" + DropDownList4.Text + "'";
        SqlDataReader myDataReader = mysqlcommand.ExecuteReader();
        myDataReader.Read();
        TextBox5.Text = myDataReader.GetValue(0).ToString();
        myDataReader.Close();
        mysqlconnection.Close();
    }
    protected void Button3_Click1(object sender, EventArgs e)
    {
        mysqlcommand = mysqlconnection.CreateCommand();
        mysqlconnection.Open();
        mysqlcommand.CommandText = "delete 成绩表 where 成绩表.课程号='" + TextBox2.Text + "' and 成绩表.任课教师编号='"+DropDownList4.Text+"'　and 成绩表.日期='" + TextBox6.Text + "'";
        int returnValue = (int)mysqlcommand.ExecuteNonQuery();
        if (returnValue != 0)
        {
            Response.Write("<script>alert('删除成功!');</script>");
            load();
        }
        else
            Response.Write("<script>alert('未知错误!');</script>");
    }
}