【发布时间】：2013-03-28 15:10:10
【问题描述】：
我尝试模拟一个运行时间较长的过程。在我的应用程序中，我使用背景并动态添加进度条。当我点击开始按钮时，一个进程开始并在面板上添加了一个进度条。如果我只单击一次，则一切正常，但如果我单击两次或更多，则添加该数量的进度条，但最后一个进度条进度增加，最后其他进度条进度突然增加。
我希望添加任何数量的进度条都应该同时处理，而不是最后一个和最后一个。一切都应该像许多进程在自己的上下文中同时运行一样一起运行。这是我的代码，我希望如果有人看一下，他们就能理解缺陷在哪里。请帮我修复最后添加的进度条进度增加的缺陷。如果可能，运行我的代码并查看问题。
public partial class Form2 : Form
{
MyBackgroundWorker backgroundWorker1 = null;
Dictionary<string, string> dct = new Dictionary<string, string>();
public Form2()
{
InitializeComponent();
}
private void Form2_Load(object sender, EventArgs e)
{
}
private void btnStart_Click(object sender, EventArgs e)
{
backgroundWorker1 = new MyBackgroundWorker();
backgroundWorker1.WorkerReportsProgress = true;
backgroundWorker1.DoWork += new DoWorkEventHandler(backgroundWorker1_DoWork);
backgroundWorker1.RunWorkerCompleted += new RunWorkerCompletedEventHandler(backgroundWorker1_RunWorkerCompleted);
backgroundWorker1.ProgressChanged += new ProgressChangedEventHandler(backgroundWorker1_ProgressChanged);
backgroundWorker1.RunWorkerAsync(txtNumber.Text);
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
string strID = DateTime.Now.ToString("yyyyMMdd") + DateTime.Now.ToString("hhmmss")+DateTime.Now.Millisecond.ToString();
MyBackgroundWorker tmpBg = (sender as MyBackgroundWorker);
tmpBg.Name = "bg_" + strID;
ProgressBar pb = new ProgressBar();
pb.Minimum = 0;
pb.Maximum = 100;
pb.Name = "pb_" + strID;
pb.Width = txtNumber.Width;
this.BeginInvoke((MethodInvoker)delegate
{
flowLayoutPanel1.Controls.Add(pb);
});
dct.Add(tmpBg.Name, pb.Name);
int input = int.Parse(e.Argument.ToString());
for (int i = 1; i <= input; i++)
{
Thread.Sleep(2000);
backgroundWorker1.ReportProgress(i * 10);
if (backgroundWorker1.CancellationPending)
{
e.Cancel = true;
return;
}
}
}
// This event handler updates the progress bar.
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
MyBackgroundWorker tmpBg = (sender as MyBackgroundWorker);
string strName = tmpBg.Name;
if (!string.IsNullOrEmpty(strName))
{
strName = strName.Substring(3);
ProgressBar pb = (ProgressBar)this.flowLayoutPanel1.Controls.Find(("pb_" + strName), true)[0];
pb.Value = e.ProgressPercentage;
}
}
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
MyBackgroundWorker tmpBg = (sender as MyBackgroundWorker);
string strName = tmpBg.Name;
strName = strName.Substring(3);
ProgressBar pb = (ProgressBar)this.flowLayoutPanel1.Controls.Find(("pb_" + strName), true)[0];
pb.Value = 100;
//MessageBox.Show("Done");
}
}
public class MyBackgroundWorker : System.ComponentModel.BackgroundWorker
{
public MyBackgroundWorker()
{
}
public MyBackgroundWorker(string name)
{
Name = name;
}
public string Name { get; set; }
}
更新部分
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
MyBackgroundWorker tmpBg = (sender as MyBackgroundWorker);
string strName = tmpBg.Name;
strName = strName.Substring(3);
ProgressBar pb = (ProgressBar)this.flowLayoutPanel1.Controls.Find(("pb_" + strName), true)[0];
//pb.Value = 100;
//MessageBox.Show("Done");
flowLayoutPanel1.Controls.Remove(pb);
}
【问题讨论】：
-
您可能不应该在单击按钮时将事件处理程序添加到后台工作程序。或者至少检查它是否为空并添加这种情况。尝试将它们添加到
Form2_Load而不是btnStart_Click -
是的，我做了整个后台工作者相关的代码，我移到了 form_load。我只是调用 RunWorkerAsync(txtNumber.Text);从我第一次单击时的 btnstart_click 事件开始，然后在我下次单击时就可以了，我收到错误“此 BackgroundWorker 当前很忙，无法同时运行多个任务。”我想在按钮上单击 N 次，应该没有任何问题，这就是为什么我每次都从 button_click 事件创建一个新的 BackgroundWorker 实例。有任何建议来更改代码，使我能够单击按钮 N 次而不会出现任何错误。
-
对不起，我误解了你在做什么
标签： c# progress-bar backgroundworker