这次把我写的一个分页控件贴上来。前阵子写了一个winform的数据库管理程序，用一个dataGrid显示数据库表中的所有内容，后来发现当数据库中的条目增多的时候，程序运行速度明显下降，系统占用内存也很大，决定对dataGrid做个分页，每次只取出要显示页的内容。上网搜了一下，没有找到我需要的，于是自己写了一个分页控件。
程序很简单，用的时候需要提供pageCount（页数），pageShow(显示的页数），currPage（当前页号）
控件提供一个自定义的事件LnkLblClicked，当用户点击页面链接的时候就会触发这个事件。下面是程序的源码。
using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;
namespace ActiveButton
{
/**//// <summary>
/// Summary description for PageControl.
/// </summary>
public class PageControl : System.Windows.Forms.UserControl
{
/**//// <summary>
/// Required designer variable.
/// </summary>
private int pageCount;
private int currPage;
// private int pageSize;
private int pageShow;
private int xDistance;
private bool bolPrev;
private bool bolNext;
private int start, end;
private EventHandler lnkLblClicked;
public event EventHandler LnkLblClicked
{
add{lnkLblClicked += value;}
remove{lnkLblClicked -= value;}
}
protected virtual void OnLnkLblClicked(EventArgs e)
{
if (lnkLblClicked != null)
lnkLblClicked(this,e);
}
Field#region Field
public int PageCount
{
get{return pageCount;}
set{pageCount = value;}
}
public int CurrPage
{
get{return currPage;}
set{currPage = value;}
}
// public int PageSize
// {
// get{return pageSize;}
// set{pageSize = value;}
// }
public int PageShow
{
get{return pageShow;}
set{pageShow = value;}
}
public int XDistance
{
get{return xDistance;}
set{xDistance = value;}
}
#endregion
private System.ComponentModel.Container components = null;
public PageControl()
{
// This call is required by the Windows.Forms Form Designer.
InitializeComponent();
// TODO: Add any initialization after the InitializeComponent call
}
public PageControl(int pageCount,int pageSize,int pageShow):this()
{
this.pageCount = pageCount;
// this.pageSize = pageSize;
this.pageShow = pageShow;
}
/**//// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
if(components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
Component Designer generated code#region Component Designer generated code
/**//// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.SuspendLayout();
//
// PageControl
//
this.Name = "PageControl";
this.Size = new System.Drawing.Size(320, 24);
this.Load += new System.EventHandler(this.PageControl_Load);
this.ResumeLayout(false);
}
#endregion
private void PageControl_Load(object sender, System.EventArgs e)
{
xDistance = 0;
bolPrev = pageCount > pageShow;
// currPage = pageCount;
end = pageCount;
start = Math.Max(1,end - pageShow + 1);
DrawControl();
}
private void DrawControl()
{
this.Controls.Clear();
System.Windows.Forms.Label lblPageCount = new Label();
lblPageCount.Text = "共" + pageCount + "页";
this.AddControl(lblPageCount,new Point(8,8),new Size(40,16));
int x = lblPageCount.Bounds.Right;
int y = lblPageCount.Location.Y;
System.Windows.Forms.Control currCtl = lblPageCount;
//calculate page start and end
int pageShowCount = Math.Min(pageCount,pageShow);
// start = Math.Max(1,currPage - pageShow/2);
// end = start + pageShowCount -1;
// if (pageCount - currPage < pageShow/2)
// {
// end = pageCount;
// start = pageCount - pageShowCount + 1;
// }
bolPrev = start != 1;
bolNext = end != pageCount;
if (bolPrev)
{//add Linklabel "prev"
System.Windows.Forms.LinkLabel lblPrev = new LinkLabel();
lblPrev.Text = "前一页";
x += xDistance;
((LinkLabel)lblPrev).LinkClicked += new LinkLabelLinkClickedEventHandler(lblCtl_Clicked);
this.AddControl(lblPrev,new Point(x,y),new Size(45, 16));
currCtl = lblPrev;
}
for (int i = start; i <= end; i ++)
{// add linklabel "page"
x = currCtl.Bounds.Right;
System.Windows.Forms.Control lblCtl = null;
if ( i == currPage)
lblCtl = new System.Windows.Forms.Label();
else
{
lblCtl = new System.Windows.Forms.LinkLabel();
((LinkLabel)lblCtl).LinkClicked += new LinkLabelLinkClickedEventHandler(lblCtl_Clicked);
}
lblCtl.Text = i.ToString();
x += xDistance;
this.AddControl(lblCtl,new Point(x,y),new Size(10, 16));
currCtl = lblCtl;
}
if (bolNext)
{// add linklabel "next"
System.Windows.Forms.LinkLabel lblNext = new LinkLabel();
lblNext.Text = "后一页";
x = currCtl.Bounds.Right;
x += xDistance;
((LinkLabel)lblNext).LinkClicked += new LinkLabelLinkClickedEventHandler(lblCtl_Clicked);
this.AddControl(lblNext,new Point(x,y),new Size(45, 16));
}
}
private void AddControl(Control ctlObj,Point point,Size size)
{
ctlObj.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
| System.Windows.Forms.AnchorStyles.Left)));
ctlObj.Location = point;
int x = ctlObj.Text.Length * 10;
if (ctlObj.Text.IndexOf("页") > 0 )
{
if (ctlObj.Text.IndexOf("共") >= 0)
x += 10;
else
x *= 2;
}
ctlObj.Size = new Size(x,16);
this.Controls.Add(ctlObj);
}
private void lblCtl_Clicked(object sender, System.Windows.Forms.LinkLabelLinkClickedEventArgs e)
{
if (sender is LinkLabel)
{
try
{
string lblText = ((LinkLabel)sender).Text;
if (lblText == "前一页")
{
end = start -1;
start = Math.Max(1,end - pageShow + 1);
currPage = end;
}
else if (lblText == "后一页")
{
start = end + 1;
end = Math.Min(pageCount,start + pageShow -1);
currPage = end;
}
else
{
int page = Convert.ToInt32(lblText);
currPage = page;
}
this.DrawControl();
this.OnLnkLblClicked(e);
}
catch{}
}
}
public void ReDraw()
{
bolPrev = pageCount > pageShow;
// currPage = pageCount;
end = pageCount;
start = Math.Max(1,end - pageShow + 1);
this.DrawControl();
this.OnLnkLblClicked(null);
}
}
}
