bbsdefault.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.Data.SqlClient;

namespace Example_10_5
{
	/// <summary>
	/// BBSDefault 的摘要说明。
	/// </summary>
	public class BBSDefault : System.Web.UI.Page
	{
		protected System.Web.UI.WebControls.Label MaxPersonNum;
		protected System.Web.UI.WebControls.Label CurentPersonNum;
		protected System.Web.UI.WebControls.Label ItemCount;
		protected System.Web.UI.WebControls.Label PageCount;
		protected System.Web.UI.WebControls.Label PageCurrentCount;
		protected System.Web.UI.WebControls.LinkButton PageFirst;
		protected System.Web.UI.WebControls.LinkButton PagePrev;
		protected System.Web.UI.WebControls.LinkButton PageNext;
		protected System.Web.UI.WebControls.LinkButton PageLast;
		protected System.Web.UI.WebControls.Label Label7;
		protected System.Web.UI.WebControls.TextBox MoveToPageCount;
		protected System.Web.UI.WebControls.Button MoveToPageCountBtn;
		protected System.Web.UI.WebControls.RegularExpressionValidator CheckedNumber;
		protected System.Web.UI.WebControls.DataGrid myDataGrid;
	
		private const  int PAGECOUNT        = 10;
		public int nTabID = 0;
		private ArrayList aAreaID = new ArrayList();
		public static int[] AreaID = new int[PAGECOUNT];

		private static int nTotalPageCount  = 0;
		private int        nRecordCount     = 0;		
		private int nCurrentPageIndex       = 0;

		private void Page_Load(object sender, System.EventArgs e)
		{
			myDataGrid.PageSize = PAGECOUNT;

			if(Request.Params["tabId"] != null)
			{
				nTabID = Int32.Parse(Request.Params["tabId"]);
			}
			if(ViewState["CurrentPageIndex"] != null)
			{
				nCurrentPageIndex = Int32.Parse(ViewState["CurrentPageIndex"].ToString());
			}
			if(Session["Index"] != null)
			{
				Session["Index"] = null;
			}
			if(Session["IsBindData"] != null)
			{
				Session["IsBindData"] = null;
			}
			if(!Page.IsPostBack)
			{	
				//绑定列表
				BindData();	
				
				//当前的页码
				PageCurrentCount.Text = (nCurrentPageIndex + 1).ToString();	

				//初始化页面导向按钮的可见性
				IsFirstLastPage();
			}
		}			

		private void BindData()
		{
			Session["IsBindData"] = "binding";

			DiscussionDB area = new DiscussionDB();
			SqlDataReader reca = area.GetAreaCount();

			if(reca.Read())
			{
				nRecordCount = Int32.Parse(reca["AreaCount"].ToString());
			}
			reca.Close();

			nTotalPageCount = nRecordCount / PAGECOUNT;
			if(nTotalPageCount * PAGECOUNT < nRecordCount)
			{
				nTotalPageCount++;
			}

			//总共的页数
			PageCount.Text = nTotalPageCount.ToString() + " ";
			ItemCount.Text = nRecordCount.ToString() + " ";
			
			DataSet ds = area.GetAreaDataSet(nCurrentPageIndex * PAGECOUNT,PAGECOUNT);

			foreach(DataRow row in ds.Tables[0].Rows)
			{
				aAreaID.Add(row.ItemArray[0]);
			}
			for(int i = 0; i < PAGECOUNT && i< aAreaID.Count; i++)
			{
				AreaID[i] = Int32.Parse(aAreaID[i].ToString());
			}

			myDataGrid.DataSource = ds;
			myDataGrid.DataBind();
		}

		public String FormatName(String sRealName,String sUserName)
		{
			if(sRealName.ToString() == "")
			{
				return(sUserName);
			}
			else
			{
				return(sRealName);
			}
		}

		/// <summary>
		/// 实现分页机制
		/// </summary>
		private void Page_Click(object sender, System.EventArgs e)
		{
		　　String commangArg = ((LinkButton)sender).CommandArgument;

			switch(commangArg)
			{
					//首页
				case "First":
				{
					nCurrentPageIndex = 0;
					break;
				}

					//上一页
				case "Prev":
				{
					nCurrentPageIndex = (int)Math.Max(0,nCurrentPageIndex - 1);
					break;
				}

					//下一页
				case "Next":
				{ 
					nCurrentPageIndex = (int)Math.Min(nTotalPageCount -1,nCurrentPageIndex +1);
					break;
				}

					//最后一页
				case "Last":
				{
					nCurrentPageIndex = nTotalPageCount -1;
					break;
				}
				default:
				{
					break;
				}
			}

			ViewState["CurrentPageIndex"] = nCurrentPageIndex.ToString();

			//重新绑定myDataGrid的数据
			BindData();

			//重新绑定当前的页码			
			PageCurrentCount.Text = (nCurrentPageIndex + 1).ToString();	

			//控制页面导向按钮的可见性
　　　　　　IsFirstLastPage();
		}

		//控制页面导向按钮的可见性
		private void IsFirstLastPage()
		{
			if(nTotalPageCount != 1)
			{
				if(nCurrentPageIndex == 0)
				{
					PagePrev.Visible = false;
				}
				else
				{
					PagePrev.Visible = true;
				}
				if(nCurrentPageIndex == nTotalPageCount -1)
				{
					PageNext.Visible = false;
				}
				else
				{
					PageNext.Visible = true;
				}
			}
			else
			{
				PagePrev.Visible = false;
				PageNext.Visible = false;
			}
		}

		//实现随机定位页面
		private void MoveToPageCountBtn_Click(object sender, System.EventArgs e)
		{
			if((MoveToPageCount.Text.Trim() != "")&&(MoveToPageCount.Text.Trim() != null))
			{
				if((Int32.Parse(MoveToPageCount.Text.Trim()) > 0)&&(Int32.Parse(MoveToPageCount.Text.Trim()) <= nTotalPageCount))
				{
					nCurrentPageIndex = Int32.Parse(MoveToPageCount.Text.Trim()) -1;
					BindData();

					//重新绑定当前的页码
					PageCurrentCount.Text = (nCurrentPageIndex + 1).ToString();

					//控制页面导向按钮的可见性
　　　　　　        IsFirstLastPage();
				}
				else
				{
					Response.Write("<script>alert(\"你输入的页码值超出页码的范围，请重新输入！\")</script>");
				}
			}
			else
			{
				Response.Write("<script>alert(\"请输入你要转到的页码！\")</script>");
			}
		}

		#region Web 窗体设计器生成的代码
		override protected void OnInit(EventArgs e)
		{
			//
			// CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
			//
			InitializeComponent();
			base.OnInit(e);
		}
		
		/// <summary>
		/// 设计器支持所需的方法 - 不要使用代码编辑器修改
		/// 此方法的内容。
		/// </summary>
		private void InitializeComponent()
		{    
			this.PageFirst.Click += new System.EventHandler(this.Page_Click);
			this.PagePrev.Click += new System.EventHandler(this.Page_Click);
			this.PageNext.Click += new System.EventHandler(this.Page_Click);
			this.PageLast.Click += new System.EventHandler(this.Page_Click);
			this.MoveToPageCountBtn.Click += new System.EventHandler(this.MoveToPageCountBtn_Click);
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion
	}
}