//frmA: 源窗体//------------------------------------------//引用using System.Threading;

BackgroundWorker worker;    

public frmA()        {            InitializeComponent();            worker = new BackgroundWorker();            worker.DoWork += new DoWorkEventHandler(worker_DoWork);            worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(worker_RunWorkerCompleted);        }        /// 
        /// 异步 开始事件        /// 
        ///         ///         private void worker_DoWork(object sender, DoWorkEventArgs e)        {            //需要执行的代码

Thread.Sleep(5000);  //让进程上卡5秒钟

}        /// 
        /// 事件: 异步执行完成后         /// 
        ///         ///         private void worker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)        {            MessageBox.Show("执行完成。", "run", MessageBoxButtons.OK, MessageBoxIcon.Information);        }       //点击一个按钮后开始执行       private void btnA_Click(object sender, EventArgs e)        {

//按钮要执行的代码放在 worker_DoWork  事件中执行

//异步执行开始            worker.RunWorkerAsync();

//显示进度窗体            frmB frm = new frmB(this.worker);            frm.StartPosition = FormStartPosition.CenterScreen;            frm.ShowDialog(this);        }frmB: //里面放了一个loading.gif图片显示进度------------------------------------------------------------using System;using System.ComponentModel;using System.Windows.Forms;namespace test{    public partial class frmB: Form    {        public frmB(BackgroundWorker worker)        {            InitializeComponent();            worker.ProgressChanged +=new ProgressChangedEventHandler(worker_ProgressChanged);            worker.RunWorkerCompleted +=new RunWorkerCompletedEventHandler(worker_RunWorkerCompleted);        }        void worker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)        {            this.Close();        }        void worker_ProgressChanged(object sender, ProgressChangedEventArgs e)        {            //lblStatus.Text = "";        }        //工作完成后执行的事件          public void OnProcessCompleted(object sender, EventArgs e)          {            this.Close();          }      }

　　二：在弹出的窗体里显示backgroundWorker的进度

1, backgroundWorker1的WorkerReportsProgress属性设置为true2, 写如下事件              private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)        {             progressBar.Value = e.ProgressPercentage;        }  progressBar是进度条是你定义的变量..可以写在后台执行里面控制3 .在后台执行里面 backgroundWorker1.ReportProgress(50);其中50就是进度调的百分比.比如一个循环循环100次没次backgroundWorker1.ReportProgress(循环次数);那么效果出来 。。 哈哈