如何解决"线程间操作无效"问题?

[ivanho]

报错:线程间操作无效: 从不是创建控件“...”的线程访问它。


if (listBox1.SelectedIndex == 7)
{
string pal = _yhdm + "$" + _yhmc + "$" + _jczbh;
Process pro = new Process();
pro = Process.Start("VEH.JCZX_Query.exe", pal);
this.Hide();

pro.Exited += new EventHandler(pro_Exited);
pro.EnableRaisingEvents = true;
//pro.WaitForExit();

}
我就是这样起动一个EXE. 然后在这个EXE线程结束时用这个方法:
void pro_Exited(object sender, EventArgs e)
{ this.Show(); }
令主窗体再显出来,但却出现了报错!!!

请帮帮忙...

[whycom]

namespace Microsoft.Samples.DirectorySearcher
{
   using System;
   using System.IO;
   using System.Threading;
   using System.Windows.Forms;

   /// <summary>
   ///      This class is a Windows Forms control that implements a simple directory searcher.
   ///      You provide, through code, a search string and it will search directories on
   ///      a background thread, populating its list box with matches.
   /// </summary>
   public class DirectorySearcher : Control
   {
      // Define a special delegate that handles marshaling
      // lists of file names from the background directory search
      // thread to the thread that contains the list box.
      private delegate void FileListDelegate(string[] files, int startIndex, int count);

      private ListBox listBox;
      private string  searchCriteria;
      private bool searching;
      private bool deferSearch;
      private Thread searchThread;
      private FileListDelegate fileListDelegate;
      private EventHandler onSearchComplete;

      public DirectorySearcher()
      {
         listBox = new ListBox();
         listBox.Dock = DockStyle.Fill;

         Controls.Add(listBox);

         fileListDelegate = new FileListDelegate(AddFiles);
         onSearchComplete = new EventHandler(OnSearchComplete);
      }

      public string SearchCriteria 
      {
         get 
         {
            return searchCriteria;
         }
         set 
         {
            // If currently searching, abort
            // the search and restart it after
            // setting the new criteria.
            //
            bool wasSearching = Searching;
            
            if (wasSearching)
            {
               StopSearch();
            }

            listBox.Items.Clear();
            searchCriteria = value;

            if (wasSearching)
            {
               BeginSearch();
            }
         }
      }

      public bool Searching 
      {
         get 
         {
            return searching;
         }
      }

      public event EventHandler SearchComplete;

      /// <summary>
      /// This method is called from the background thread. It is called through
      /// a BeginInvoke call so that it is always marshaled to the thread that
      /// owns the list box control.
      /// </summary>
      /// <param name="files"></param>
      /// <param name="startIndex"></param>
      /// <param name="count"></param>
      private void AddFiles(string[] files, int startIndex, int count)
      {
         while(count-- > 0)
         {
            listBox.Items.Add(files[startIndex + count]);
         }
      }

      public void BeginSearch() 
      {
         // Create the search thread, which 
         // will begin the search.
         // If already searching, do nothing.
         //
         if (Searching)
         {
            return;
         }

         // Start the search if the handle has
         // been created. Otherwise, defer it until the
         // handle has been created.
         if (IsHandleCreated)
         {
            searchThread = new Thread(new ThreadStart(ThreadProcedure));
            searching = true;
            searchThread.Start();
         }
         else
         {
            deferSearch = true;
         }
      }

      protected override void OnHandleDestroyed(EventArgs e)
      {
         // If the handle is being destroyed and you are not
         // recreating it, then abort the search.
         if (!RecreatingHandle)
         {
            StopSearch();
         }
         base.OnHandleDestroyed(e);
      }

      protected override void OnHandleCreated(EventArgs e) 
      {
         base.OnHandleCreated(e);
         if (deferSearch)
         {
            deferSearch = false;
            BeginSearch();
         }
      }

      /// <summary>
      /// This method is called by the background thread when it has finished
      /// the search.
      /// </summary>
      /// <param name="sender"></param>
      /// <param name="e"></param>
      private void OnSearchComplete(object sender, EventArgs e)
      {
         if (SearchComplete != null)
         {
            SearchComplete(sender, e);
         }
      }

      public void StopSearch()
      {
         if (!searching)
         {
            return;
         }

         if (searchThread.IsAlive)
         {
            searchThread.Abort();
            searchThread.Join();
         }

         searchThread = null;
         searching = false;
      }

      /// <summary>
      /// Recurses the given path, adding all files on that path to 
      /// the list box. After it finishes with the files, it
      /// calls itself once for each directory on the path.
      /// </summary>
      /// <param name="searchPath"></param>
      private void RecurseDirectory(string searchPath)
      {
         // Split searchPath into a directory and a wildcard specification.
         //
         string directory = Path.GetDirectoryName(searchPath);
         string search = Path.GetFileName(searchPath);

         // If a directory or search criteria are not specified, then return.
         //
         if (directory == null || search == null)
         {
            return;
         }

         string[] files;
         
         // File systems like NTFS that have
         // access permissions might result in exceptions
         // when looking into directories without permission.
         // Catch those exceptions and return.
         try 
         {
            files = Directory.GetFiles(directory, search);
         }
         catch(UnauthorizedAccessException)
         {
            return;
         }
         catch(DirectoryNotFoundException)
         {
            return;
         }

         // Perform a BeginInvoke call to the list box
         // in order to marshal to the correct thread. It is not
         // very efficient to perform this marshal once for every
         // file, so batch up multiple file calls into one
         // marshal invocation.
         int startingIndex = 0;

         while(startingIndex < files.Length)
         {
            // Batch up 20 files at once, unless at the
            // end.
            //
            int count = 20;
            if (count + startingIndex >= files.Length)
            {
               count = files.Length - startingIndex;
            }

            // Begin the cross-thread call. Because you are passing
            // immutable objects into this invoke method, you do not have to
            // wait for it to finish. If these were complex objects, you would
            // have to either create new instances of them or 
            // wait for the thread to process this invoke before modifying
            // the objects.
            IAsyncResult r = BeginInvoke(fileListDelegate, new object[] {files, startingIndex, count});
            startingIndex += count;
         }

         // Now that you have finished the files in this directory, recurse for
         // each subdirectory.
         string[] directories = Directory.GetDirectories(directory);
         foreach(string d in directories)
         {
            RecurseDirectory(Path.Combine(d, search));
         }
      }

      /// <summary>
      /// This is the actual thread procedure. This method runs in a background
      /// thread to scan directories. When finished, it simply exits.
      /// </summary>
      private void ThreadProcedure()
      {
         // Get the search string. Individual 
         // field assigns are atomic in .NET, so you do not
         // need to use any thread synchronization to grab
         // the string value here.
         try 
         {
            string localSearch = SearchCriteria;

            // Now, search the file system.
            //
            RecurseDirectory(localSearch);
         }
         finally
         {
            // You are done with the search, so update.
            //
            searching = false;

            // Raise an event that notifies the user that
            // the search has terminated.  
            // You do not have to do this through a marshaled call, but
            // marshaling is recommended for the following reason:
            // Users of this control do not know that it is
            // multithreaded, so they expect its events to 
            // come back on the same thread as the control.
            BeginInvoke(onSearchComplete, new object[] {this, EventArgs.Empty});
         }
      }
   }
}

[绿色夹克衫]

Invoke一下更健康

[ivanho]

看过几篇于Invoke的文章,但是看不懂..可有实例...

[派大奇]

试试 在 主窗体的 构造函数里加

System.Windows.Forms.Control.CheckForIllegalCrossThreadCalls = false;

[hezison]

            void pro_Exited(object sender, EventArgs e)
            {
                this.Invoke(new EventHandler(delegate(object sender1,EventArgs e1){this.Show()}));
            }

[dpcrman1987]

诶，受教了

[number1170196649]

我也遇到了这个问题，但是Invoke不会用。