st_sortcourse.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_sortcourse : System.Web.UI.Page
{
    SqlConnection st_conn1;
    string st_sqlstr;
    protected void Page_Load(object sender,EventArgs e)
    {
        string st_connstr = ConfigurationManager.AppSettings["st_dbconn"];
        st_conn1 = new SqlConnection(st_connstr);
        if (!IsPostBack)
        {
            //课程名称下拉列表框绑定

            SqlConnection st_conn2 = new SqlConnection(st_connstr);
            st_conn2.Open();
            string st_sql1 = "select * from ST_course where ST_Course_kind='2'";
            SqlCommand st_comm1 = new SqlCommand(st_sql1, st_conn2);
            SqlDataReader st_dr = st_comm1.ExecuteReader();
            st_ddl_course.Items.Add(new ListItem("", ""));
            while (st_dr.Read())
            {
                st_ddl_course.Items.Add(new ListItem(st_dr["ST_Course_name"].ToString(), st_dr["ST_Course_id"].ToString()));
            }
            st_conn2.Close();

        }
    }
    protected void st_btn_sort_Click(object sender, EventArgs e)
    {
        //在数据库中找出选此课的总人数
        string st_sqlstr = "select COUNT(ST_Student_id) from ST_student_course where ST_Course_id='" + st_tbx_courseid.Text + "' and ST_Course_year='" + st_tbx_year.Text + "'";
        SqlCommand st_comm1 = new SqlCommand(st_sqlstr, st_conn1);
        st_conn1.Open();
        SqlDataReader st_dr1 = st_comm1.ExecuteReader();
        if (st_dr1.Read())
        {
            st_lbl_all.Text = "选此课总人数为：" + st_dr1[0].ToString();
        }
        else
        {
            st_lbl_all.Text = "无人选此课";
        }
        st_pn_yes.Visible = true;
        st_conn1.Close();
    }
    protected void st_btn_yes_Click(object sender, EventArgs e)
    {
        st_sqlstr = "insert into ST_student_course(ST_Student_id,ST_Course_id,ST_Course_year) values(@Student_id,@Course_id,@Course_year)";
        SqlCommand st_comm = new SqlCommand(st_sqlstr, st_conn1);
        st_comm.Parameters.Add(new SqlParameter("@Student_id", SqlDbType.VarChar, 50));
        st_comm.Parameters.Add(new SqlParameter("@Course_id", SqlDbType.VarChar, 50));
        st_comm.Parameters.Add(new SqlParameter("@Course_year", SqlDbType.VarChar, 50));
        st_comm.Parameters["@Student_id"].Value = Session["User_id"].ToString();
        st_comm.Parameters["@Course_id"].Value = st_tbx_courseid.Text;
        st_comm.Parameters["@Course_year"].Value = st_tbx_year.Text;
        st_conn1.Open();
        try
        {
            st_comm.ExecuteNonQuery();
        }
        catch (SqlException)
        {
            st_lbl_note.Text = "添加失败!";
        }

        st_conn1.Close();
		
    }
    protected void st_btn_no_Click(object sender, EventArgs e)
    {
        st_lbl_all.Text = "请重新选择";
    }
    protected void st_btn_look_Click(object sender, EventArgs e)
    {
        if (st_ddl_course.SelectedItem.Text == "")
        {
            if (st_tbx_teacher.Text == "")
            {
                st_sqlstr = "select ST_course.ST_Course_name,ST_course.ST_Course_id,ST_teacher.ST_Teacher_name,ST_course.ST_Course_credit,ST_course.ST_Course_period from ST_course,ST_teacher,ST_teacher_course where ST_teacher_course.ST_Course_year='" + st_tbx_term.Text + "' and ST_teacher_course.ST_Course_id=ST_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id";
            }
            else
            {
                st_sqlstr = "select ST_course.ST_Course_name,ST_course.ST_Course_id,ST_teacher.ST_Teacher_name,ST_course.ST_Course_credit,ST_course.ST_Course_period from ST_course,ST_teacher,ST_teacher_course where ST_teacher_course.ST_Course_year='" + st_tbx_term.Text + "' and ST_teacher_course.ST_Course_id=ST_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_teacher.ST_Teacher_name='" + st_tbx_teacher.Text + "'";

            }
        }
        else
        {
            if (st_tbx_teacher.Text == "")
            {
                st_sqlstr = "select ST_course.ST_Course_name,ST_course.ST_Course_id,ST_teacher.ST_Teacher_name,ST_course.ST_Course_credit,ST_course.ST_Course_period from ST_course,ST_teacher,ST_teacher_course where ST_teacher_course.ST_Course_year='" + st_tbx_term.Text + "' and ST_teacher_course.ST_Course_id=ST_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_course.ST_Course_name='" + st_ddl_course.SelectedItem.Text + "'";

            }
            else
            {
                st_sqlstr = "select ST_course.ST_Course_name,ST_course.ST_Course_id,ST_teacher.ST_Teacher_name,ST_course.ST_Course_credit,ST_course.ST_Course_period from ST_course,ST_teacher,ST_teacher_course where ST_teacher_course.ST_Course_year='" + st_tbx_term.Text + "' and ST_teacher_course.ST_Course_id=ST_course.ST_Course_id and ST_teacher_course.ST_Teacher_id=ST_teacher.ST_Teacher_id and ST_course.ST_Course_name='" + st_ddl_course.SelectedItem.Text + "' and ST_teacher.ST_Teacher_name='" + st_tbx_teacher.Text + "'";

            }
        }
        SqlDataAdapter st_da = new SqlDataAdapter(st_sqlstr, st_conn1);
        DataSet st_ds = new DataSet();
        st_da.Fill(st_ds);
        st_dtg_sort.DataSource = st_ds;
        st_dtg_sort.DataBind();
    }
    private void st_cv_course_ServerValidate(object source, System.Web.UI.WebControls.ServerValidateEventArgs args)
    {
        st_conn1.Open();
        st_sqlstr = "select * from ST_course where ST_Course_id='" + st_tbx_courseid.Text + "'";
        SqlCommand st_comm = new SqlCommand(st_sqlstr, st_conn1);
        SqlDataReader st_dr1 = st_comm.ExecuteReader();
        if (st_dr1.Read())
        {
            args.IsValid = true;
        }
        else
        {
            args.IsValid = false;
        }
        st_conn1.Close();
    }
}