myviewstate.aspx.cs

ASP C#代码实例 适合初学人士学习使用

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Configuration;
using System.Data.SqlClient;

namespace Example_13_3
{
	/// <summary>
	/// Summary description for MyViewState.
	/// </summary>
	public class MyViewState : System.Web.UI.Page
	{
		protected System.Web.UI.WebControls.Button SetViewState;
		protected System.Web.UI.WebControls.Label ViewStateMsg;
		protected System.Web.UI.WebControls.DataGrid viewStateDG;
		private readonly string SQLCONNECTIONSTRING = ConfigurationSettings.AppSettings["SQLCONNECTIONSTRING"].ToString();
	
		private void Page_Load(object sender, System.EventArgs e)
		{
			if(!Page.IsPostBack)
			{
				///绑定DataGrid控件的数据
				GetStaffs();
			}
		}

		private void GetStaffs()
		{
			///从数据库中Tabs表获取所有记录
			String cmdText = "SELECT TOP 10 * FROM Staff ORDER BY Staff_ID";
			SqlConnection myConnection = new SqlConnection(SQLCONNECTIONSTRING);
			SqlCommand myCommand = new SqlCommand(cmdText,myConnection);

			///执行数据库查询
			myConnection.Open();
			SqlDataReader dr = myCommand.ExecuteReader();
			
			///绑定DataGrid控件的数据
			viewStateDG.DataSource = dr;
			viewStateDG.DataBind();

			///关闭读取器和数据库的链接
			dr.Close();
			myConnection.Close();
		}

		#region Web Form Designer generated code
		override protected void OnInit(EventArgs e)
		{
			//
			// CODEGEN: This call is required by the ASP.NET Web Form Designer.
			//
			InitializeComponent();
			base.OnInit(e);
		}
		
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{    
			this.SetViewState.Click += new System.EventHandler(this.SetViewState_Click);
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion

		private void SetViewState_Click(object sender, System.EventArgs e)
		{
			if(viewStateDG.EnableViewState == true)
			{
				viewStateDG.EnableViewState = false;
				ViewStateMsg.Text = "控件viewStateDG的ViewState=false";
			}
			else
			{
				viewStateDG.EnableViewState = true;
				ViewStateMsg.Text = "控件viewStateDG的ViewState=true";
			}

			///绑定DataGrid控件的数据
			GetStaffs();
		}
	}
}