java web 进度条_教你制做Web实时进度条

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：

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 description for _Default.

///

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);

}

/**

/// Required method for Designer support - do not modify

/// the contents of this method with the code editor.

///

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("

sbScript.Append("\n");

sbScript.Append("\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

ForeColor="Silver">

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 description for Progress.

///

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("","");

}

if(state==100)

{

this.panelProgress.Visible = false;

this.panelBarSide.Visible = false;

this.lblMessages.Text = "Task Completed!";

Page.RegisterStartupScript("","");

}

}

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);

}

/**

/// Required method for Designer support - do not modify

/// the contents of this method with the code editor.

///

private void InitializeComponent()

{

this.Load += new System.EventHandler(this.Page_Load);

}

#endregion

}

}

posted on 2007-03-23 10:28 圣域飞侠 阅读(188) 评论(0)  编辑  收藏 所属分类: 转载