Question

添加了这个课程：

public class MyProgress
        {
            public string Id { get; set; }
            public string Progress { get; set; }
        }

dowork事件：

private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
        {            
            BackgroundWorker worker = sender as BackgroundWorker;

            if ((worker.CancellationPending == true))
            {
                e.Cancel = true;
            }
            else
            {
                List<IntPtr> intptrs = GetProcessesIntptrList();
                for (int x = 0; x < intptrs.Count ; x++)
                {
                    GetProcessInfo(intptrs[x]);
                }
                    while (true)
                    {
                        List<MyProgress> prog = new List<MyProgress>();

                        prog = new List<MyProgress>();

                        procList = Process.GetProcesses().ToList();
                        for (int i = 0; i < procList.Count; i++)
                        {
                            Process[] processes = Process.GetProcessesByName(procList[i].ProcessName);
                            PerformanceCounter performanceCounter = new PerformanceCounter();
                            performanceCounter.CategoryName = "Process";
                            performanceCounter.CounterName = "Working Set - Private";//"Working Set";
                            performanceCounter.InstanceName = processes[0].ProcessName;

                            prog.Add(new MyProgress { Id = procList[i].ProcessName, Progress = ((uint)performanceCounter.NextValue() / 1024).ToString("N0") });

                            worker.ReportProgress(0, prog);
                        }
                    }
            }
        }

并上一次backgroundworker progresschanged事件，我希望将每个进程的值添加到单元格3下的datagridview1行。

private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            foreach (MyProgress p in (e.UserState as List<MyProgress>))
            {
                currentRow.Cells[3].Value = p.Progress;
                dataGridView1.Rows.Add(
                    p.Progress);
            }
        }

变量currentRow尚不存在。我知道单元格3是我想要添加进程值的所有行的地方。

而且我也不知道应该有多少行。以及如何将每个过程值报告到单元格3下的一行？

我在progresschanged事件中试过这个：

private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            foreach (MyProgress p in (e.UserState as List<MyProgress>))
            {
                int rowIdx = dataGridView1.Rows.Add();
                dataGridView1.Rows[rowIdx].Cells[3].Value = p.Progress;
            }
        }

但我在foreach上获得例外：例外是：

Additional information: Collection was modified; enumeration operation may not execute.

System.InvalidOperationException was unhandled by user code
  HResult=-2146233079
  Message=Collection was modified; enumeration operation may not execute.
  Source=mscorlib
  StackTrace:
       at System.Collections.Generic.List`1.Enumerator.MoveNextRare()
       at Automation.Form1.backgroundWorker1_ProgressChanged(Object sender, ProgressChangedEventArgs e) in d:\C-Sharp\Automation\Automation\Automation\Form1.cs:line 719
  InnerException:

Answer 1

据我了解你的问题，你需要这个

Integer rowIdx = dataGridView1.Rows.Add();
dataGridView1.Rows[rowIdx].Cells[3].Value = p.Progress

为什么错误？ - 这是因为你有设计缺陷 - 在backgroundWorker1_DoWork，它在后台线程上运行，你仍在修改集合，同时你转移到progress事件。会发生什么，当你在一个线程上迭代它时，另一个线程会添加项目。您需要做的是复制，传递此副本并重复此副本。这是使用数组

执行此操作的一种简单方法

 . . . . 
     MyProgress[] arrP;
     prog.CopyTo(arrP);
     worker.ReportProgress(0, arrP);
 . . . 


private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{

    MyProgress[] progArr  = (MyProgress[])e.UserState;
    foreach (MyProgress p in progArr)
    {
        int rowIdx = dataGridView1.Rows.Add();
            dataGridView1.Rows[rowIdx].Cells[3].Value = p.Progress;
    }
}

我不确定这整个设计，所以我不想改变它。只是说现在有什么不对，不是一般的。

如何从backgroundworker dowork事件向dataGridView报告多个reportprogress值？

1 个答案: