Question

首先在form1顶部：

FileInfo[] allfiles;
string mainDirectory;

然后在form1构造函数中：

mainDirectory = @"c:\temp\screens7\";
var directory = new DirectoryInfo(mainDirectory);
allfiles = directory.GetFiles();
trackBar1.Minimum = 0;
trackBar1.Maximum = allfiles.Length;

然后按钮点击事件：

private void button1_Click(object sender, EventArgs e)
        {
            if (allfiles.Length > 1)
            {
                backgroundWorker1.RunWorkerAsync();
            }
        }

背景工作者dowork事件：

private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
        {
            CreateAvi.AviMovie(allfiles,backgroundWorker1);
        }

Progresschanged事件：

private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            progressBar1.Value = e.ProgressPercentage;
            label9.Invoke(new MethodInvoker(delegate { label9.Text = allfiles[e.ProgressPercentage].FullName; }));

        }

然后在另一个类中，我在一个方法中有这个循环：

public static void AviMovie(FileInfo[] FileNames,BackgroundWorker bgw1)
        {
            try
            {
                Bitmap bitmap = (Bitmap)Image.FromFile(FileNames[0].FullName);
                AviManager aviManager =
                    new AviManager(@"c:\temp\new.avi", false);
                VideoStream aviStream =
                    aviManager.AddVideoStream(false, 25, bitmap);
                int count = 0;
                for (int n = 0; n < FileNames.Length; n++)
                {
                    if (FileNames[n].Length > 0)
                    {
                        bitmap =
                           (Bitmap)Bitmap.FromFile(FileNames[n].FullName);
                        aviStream.AddFrame(bitmap);
                        bitmap.Dispose();
                        count++;
                        int pctDone = count * 100 / FileNames.Length;
                        bgw1.ReportProgress(count);
                    }
                }
                aviManager.Close();
            }
            catch
            {
                string t = "error";
            }
        }

我做了一些改变：

在AviMovie方法的新类中，我添加了bgw1变量。报告进展如下：ReportProgress（pctDown）
在进度改变事件的form1中，它是：

private void backgroundWorker1_ProgressChanged（object sender，ProgressChangedEventArgs e） { progressBar1.Value = e.ProgressPercentage; }

当它是这样的时候，progressBar结束了100％但后来我想报告并在label9上显示文件，命名新类中AviMovie方法的每个文件名。

首先我做了：

label9.Text = allfiles[e.ProgressPercentage].FullName;

然后我添加了Invoke。

现在的问题是它从未在167中的文件101上始终显示正确的文件。进度条也在结束前停了一点。所有这些问题都发生在我开始使用label9时。

当它在几秒钟之后在文件101结束前稍微停止时它会抛出异常：

System.Reflection.TargetInvocationException was unhandled
  HResult=-2146232828
  Message=Exception has been thrown by the target of an invocation.
  Source=mscorlib
  StackTrace:
       at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
       at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
       at System.Reflection.RuntimeMethodInfo.UnsafeInvoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
       at System.Delegate.DynamicInvokeImpl(Object[] args)
       at System.Windows.Forms.Control.InvokeMarshaledCallbackDo(ThreadMethodEntry tme)
       at System.Windows.Forms.Control.InvokeMarshaledCallbackHelper(Object obj)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Windows.Forms.Control.InvokeMarshaledCallback(ThreadMethodEntry tme)
       at System.Windows.Forms.Control.InvokeMarshaledCallbacks()
       at System.Windows.Forms.Control.WndProc(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
       at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
       at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
       at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.Run(Form mainForm)
       at WindowsFormsApplication1.Program.Main() in d:\C-Sharp\ReadWriteToMemory\WindowsFormsApplication1\WindowsFormsApplication1\Program.cs:line 19
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: System.ArgumentOutOfRangeException
       HResult=-2146233086
       Message=Value of '101' is not valid for 'Value'. 'Value' should be between 'minimum' and 'maximum'.
Parameter name: Value
       Source=System.Windows.Forms
       ParamName=Value
       StackTrace:
            at System.Windows.Forms.ProgressBar.set_Value(Int32 value)
            at WindowsFormsApplication1.Form1.backgroundWorker1_ProgressChanged(Object sender, ProgressChangedEventArgs e) in d:\C-Sharp\ReadWriteToMemory\WindowsFormsApplication1\WindowsFormsApplication1\Form1.cs:line 292
            at System.ComponentModel.BackgroundWorker.OnProgressChanged(ProgressChangedEventArgs e)
            at System.ComponentModel.BackgroundWorker.ProgressReporter(Object arg)
       InnerException:

这很奇怪，因为在form1构造函数中我将progreaaBar1的最大值设置为allfile.Lenght 最小值为0.所以我现在在form1设计器中将progressBar1更改为mnimum 0，最大1000我将其设置为1000仅用于测试。

当我在设计师中将它设置为最大1000时，它就像它想要的那样达到167但是最后又抛出另一个例外：

System.Reflection.TargetInvocationException was unhandled
  HResult=-2146232828
  Message=Exception has been thrown by the target of an invocation.
  Source=mscorlib
  StackTrace:
       at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
       at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
       at System.Reflection.RuntimeMethodInfo.UnsafeInvoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
       at System.Delegate.DynamicInvokeImpl(Object[] args)
       at System.Windows.Forms.Control.InvokeMarshaledCallbackDo(ThreadMethodEntry tme)
       at System.Windows.Forms.Control.InvokeMarshaledCallbackHelper(Object obj)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Windows.Forms.Control.InvokeMarshaledCallback(ThreadMethodEntry tme)
       at System.Windows.Forms.Control.InvokeMarshaledCallbacks()
       at System.Windows.Forms.Control.WndProc(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
       at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
       at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
       at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.Run(Form mainForm)
       at WindowsFormsApplication1.Program.Main() in d:\C-Sharp\ReadWriteToMemory\WindowsFormsApplication1\WindowsFormsApplication1\Program.cs:line 19
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: System.IndexOutOfRangeException
       HResult=-2146233080
       Message=Index was outside the bounds of the array.
       Source=System.Windows.Forms
       StackTrace:
            at System.Windows.Forms.Control.MarshaledInvoke(Control caller, Delegate method, Object[] args, Boolean synchronous)
            at System.Windows.Forms.Control.Invoke(Delegate method, Object[] args)
            at System.Windows.Forms.Control.Invoke(Delegate method)
            at WindowsFormsApplication1.Form1.backgroundWorker1_ProgressChanged(Object sender, ProgressChangedEventArgs e) in d:\C-Sharp\ReadWriteToMemory\WindowsFormsApplication1\WindowsFormsApplication1\Form1.cs:line 293
            at System.ComponentModel.BackgroundWorker.OnProgressChanged(ProgressChangedEventArgs e)
            at System.ComponentModel.BackgroundWorker.ProgressReporter(Object arg)
       InnerException:

这是form1中的第292行：

progressBar1.Value = e.ProgressPercentage;

这是form1中的第293行：

label9.Invoke(new MethodInvoker(delegate { label9.Text = allfiles[e.ProgressPercentage].FullName; }));

为什么我需要在设计器中将progressBar1最大值更改为1000，如果我将其更改为allfiles.Lenght已经在构造函数中？否则它将在文件101处停止并使用mininmum和maximum来抛出异常。

第二个例外是什么？我怎样才能修复所有这些label9文件名称报告？在新类中的AviMovie方法中，我尝试了这一行：

bgw1.ReportProgress(count);

要报告计数，然后报告变量n，然后报告pctDone。在所有情况下，它只是直到文件101并抛出异常。

**它有点长，但它的所有连接试图更清楚地解释它。

Answer 1

您正在使用某种百分比索引FileInfo。您必须反转此计算才能获得正确索引数组的计数。

为什么在使用backgroundworker和progressBar并标记我获取异常和错误的进度报告？

1 个答案: