updategrade.aspx.cs

《精通ASP.NET2.0网络应用系统开发》书中的源码

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;
using StudentManager;

public partial class UpdateGrade : System.Web.UI.Page
{
	int nGradeID = -1;

	protected void Page_Load(object sender,EventArgs e)
	{
		///获取ID的值
		if (Request.Params["GradeID"] != null)
		{
			nGradeID = Int32.Parse(Request.Params["GradeID"].ToString());
		}

		if (!Page.IsPostBack)
		{
			///绑定控件的数据
			BindYearData();
			if (nGradeID > -1)
			{
				BindGradeData(nGradeID);
			}
		}

		///设置按钮的可用性
		UpdateBtn.Enabled = YearDateList.Items.Count > 0 && nGradeID >= 0 ? true : false;
	}

	private void BindYearData()
	{
		///为年列表添加40个数据项
		YearDateList.Items.Clear();
		for (int i = 0;i < 40;i++)
		{
			YearDateList.Items.Add(new ListItem((1991 + i).ToString()));
		}
	}

	private void BindGradeData(int nGradeID)
	{
		///获取数据
		Grade grade = new Grade();
		SqlDataReader recg = grade.GetSingleGrade(nGradeID);

		///读取数据
		if (recg.Read())
		{
			///显示数据
			Desn.Text = recg["Desn"].ToString();
			Semester.Text = recg["Semester"].ToString();

			ASPNET2System.SetListBoxItem(YearDateList,recg["YearDate"].ToString());
		}
		recg.Close();          ///关闭数据源
	}

	protected void UpdateBtn_Click(object sender,EventArgs e)
	{
		///如果页面输入内容合法
		if (Page.IsValid == true)
		{
			///定义类
			StudentManager.Grade grade = new StudentManager.Grade();
			try
			{
				///修改
				grade.UpdateGrade(nGradeID,Desn.Text.Trim(),
					Int32.Parse(YearDateList.SelectedItem.Text),
					Int32.Parse(Semester.Text.Trim()));

				///显示操作结果信息
				Response.Write("<script>window.alert('" + ASPNET2System.OPERATIONUPDATESUCCESSMESSAGE + "')</script>");
			}
			catch (Exception ex)
			{
				///显示修改操作中的失败、错误信息
				Response.Redirect("~/DesktopModules/ErrorPage.aspx?ErrorUrl="
					+ ASPNET2System.RedirectErrorUrl(Request.RawUrl)
					+ "&ErrorMessage=" + ex.Message.Replace("\n"," "));
			}
		}
	}

	protected void ReturnBtn_Click(object sender,EventArgs e)
	{
		///返回管理页面
		Response.Redirect("~/DesktopModules/Grade/GradeManage.aspx");
	}	
}