Web实时进度条

来源：互联网发布：网络驱动器怎么删除编辑：程序博客网时间：2024/05/16 12:10

网上已经有很多Web进度条的例子，但是很多都是估算时间，不能正真反应任务的真实进度。我自己结合多线程和ShowModalDialog制做了一个实时进度条，原理很简单：使用线程开始长时间的任务，定义一个Session，当任务进行到不同的阶段改变Session的值，线程开始的同时使用ShowModalDialog打开一个进度条窗口，不断刷新这个窗口获取Session值，反应出实时的进度。下面就来看看具体的代码：（文章结尾处下载源代码）

先新建一个Default.aspx页面，
客户端代码：

<body MS_POSITIONING="GridLayout">    <form id="Form1" method="post" runat="server">            <br>            <br>            <asp:Button id="Button1" runat="server" Text="Start Long Task!"></asp:Button>    </form></body>

服务器端代码：

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.Text;namespace WebProgressBar{    /**//// <summary>    /// Summary description for _Default.    /// </summary>    public class _Default : System.Web.UI.Page    {        protected System.Web.UI.WebControls.Button Button1;            private void Page_Load(object sender, System.EventArgs e)        {            // Put user code to initialize the page here        }        Web Form Designer generated code#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.Button1.Click += new System.EventHandler(this.Button1_Click);            this.Load += new System.EventHandler(this.Page_Load);        }        #endregion        private void LongTask()        {            //模拟长时间任务            //每个循环模拟任务进行到不同的阶段            for(int i=0;i<11;i++)            {                System.Threading.Thread.Sleep(1000);                //设置每个阶段的state值，用来显示当前的进度                Session["State"] = i+1;            }            //任务结束            Session["State"] = 100;        }        public static void OpenProgressBar(System.Web.UI.Page Page)        {            StringBuilder sbScript = new StringBuilder();            sbScript.Append("<script language='JavaScript' type='text/javascript'>/n");            sbScript.Append("<!--/n");            //需要IE5.5以上支持            sbScript.Append("window.showModalDialog('Progress.aspx','','dialogHeight: 100px; dialogWidth: 350px; edge: Raised; center: Yes; help: No; resizable: No; status: No;scroll:No;');/n");            //IE5.5以下使用window.open            //sbScript.Append("window.open('Progress.aspx','', 'height=100, width=350, toolbar =no, menubar=no, scrollbars=no, resizable=no, location=no, status=no');/n");            sbScript.Append("// -->/n");            sbScript.Append("</script>/n");            Page.RegisterClientScriptBlock("OpenProgressBar", sbScript.ToString());        }        private void Button1_Click(object sender, System.EventArgs e)        {            System.Threading.Thread thread=new System.Threading.Thread(new System.Threading.ThreadStart(LongTask));            thread.Start();            Session["State"]=1;            OpenProgressBar(this.Page);        }    }}

新建一个进度条页面Progress.aspx
客户端：
在head中加入

<base target="_self"><body MS_POSITIONING="GridLayout">        <form id="Form1" method="post" runat="server">            <asp:Label id="lblMessages" runat="server"></asp:Label>            <asp:Panel id="panelBarSide" runat="server" Width="300px" BorderStyle="Solid" BorderWidth="1px"                ForeColor="Silver">                <asp:Panel id="panelProgress" runat="server" Width="10px" BackColor="Green"></asp:Panel>            </asp:Panel>            <asp:Label id="lblPercent" runat="server" ForeColor="Blue"></asp:Label>        </form></body>

服务器端：

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;namespace WebProgressBar{    /**//// <summary>    /// Summary description for Progress.    /// </summary>    public class Progress : System.Web.UI.Page    {        protected System.Web.UI.WebControls.Label lblMessages;        protected System.Web.UI.WebControls.Panel panelProgress;        protected System.Web.UI.WebControls.Panel panelBarSide;        protected System.Web.UI.WebControls.Label lblPercent;            private int state = 0;        private void Page_Load(object sender, System.EventArgs e)        {            // Put user code to initialize the page here            if(Session["State"]!=null)            {                state = Convert.ToInt32(Session["State"].ToString());            }            else            {                Session["State"]=0;            }            if(state>0&&state<=10)            {                this.lblMessages.Text = "Task undertaking!";                this.panelProgress.Width = state*30;                this.lblPercent.Text = state*10 + "%";                Page.RegisterStartupScript("","<script>window.setTimeout('window.Form1.submit()',100);</script>");            }            if(state==100)            {                this.panelProgress.Visible = false;                this.panelBarSide.Visible = false;                this.lblMessages.Text = "Task Completed!";                Page.RegisterStartupScript("","<script>window.close();</script>");            }        }        Web Form Designer generated code#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.Load += new System.EventHandler(this.Page_Load);        }        #endregion    }}