这是DoWork：
private void uploadWorker_DoWork(object sender, DoWorkEventArgs e)
{
uploadWorker.ReportProgress(20);
int tiffError = 0;
finalFiles = Directory.GetFiles(AppVars.FinalPolicyImagesFolder);
foreach (string file in finalFiles)
{
if (!file.EndsWith(".tiff"))
{
tiffError = 1;
break;
}
}
uploadWorker.ReportProgress(50);
if (tiffError == 1)
{
MessageBox.Show("There are files in this folder that are not .tiff. Please ensure only .tiff files are in this folder.", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
if (finalFiles.Length == 0)
{
MessageBox.Show("There are no TIFF files to be uploaded. Please generate files first.", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);
pbUpload.Value = 0;
EnableAllButtons();
}
else
{
double count = finalFiles.Length;
int current = 0;
int pbValue = 0;
uploadWorker.ReportProgress(70);
foreach (string file in finalFiles)
{
current = current + 2;
if (file.Contains(".tiff") == true)
{
PolicyNumber = Path.GetFileName(file).Split('_')[0];
basePolicyNumber = PolicyNumber.Remove(PolicyNumber.Length - 2);
basePolicyNumber = basePolicyNumber + "00";
finalPolicyName = Path.GetFileName(file);
PolicyUUID = Transporter.GetPolicyUUID(AppVars.pxCentralRootURL, basePolicyNumber);
if (PolicyUUID == "")
{
MessageBox.Show("The InsightPolicyID for the policy you are trying to upload does not exist in ixLibrary. Please ensure the policy number is correct. If you are sure it should be in ixLibray, please contact IT.", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
ixLibrarySourceFileURL = AppVars.ixLibraryPolicyAttachmentsURL + finalPolicyName;
UploadToixLibraryErrorCode = Transporter.UploadFileToixLibrary(AppVars.ixLibraryPolicyAttachmentsURL, file);
if (UploadToixLibraryErrorCode != 0)
{
MessageBox.Show("There was an error uploading the file to ixLibrary. Please contact IT about this problem.", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
GeneratePayLoadErrorCode = Transformer.GeneratePayLoad(ixLibrarySourceFileURL, finalPolicyName);
if (GeneratePayLoadErrorCode != 0)
{
MessageBox.Show("There was an error generating the XML for pxCentral. Please contact IT about this problem.", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
pxCentralPOSTErrorCode = Transporter.pxCentralPOST(AppVars.pxCentralRootURL + PolicyUUID, AppVars.pxCentralXMLPayloadFilePath);
pbValue = Convert.ToInt32(((current / count) * 30) + 70);
uploadWorker.ReportProgress(pbValue);
}
}
}
}
}
}
}
}
一旦它击中了最后一个}，我在这里得到了TargetInvocationException未处理的错误（参见代码中的注释）：
static class Program
{
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
bool createdNew = false;
Mutex mutex = new Mutex(true, "MyApplicationMutex", out createdNew);
if (createdNew == true)
{
//error happens here
Application.Run(new frmMain());
}
else
{
MessageBox.Show("The application is already running.", Application.ProductName, MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
}
}
}
我不知道为什么这一切突然发生了。有谁知道为什么？
最后，这是RunWorkerCompleted：
private void uploadWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Error == null)
{
DeleteFinalFiles(finalFiles);
MessageBox.Show("Upload process complete.", "Complete!", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
EnableAllButtons();
}
答案 0 :(得分：3)
您正在EnableAllButtons处理程序中调用DoWork。据推测，这会改变表单上按钮的Enabled状态。从UI线程以外的任何其他线程都不合法。您应该在EnableAllButtons事件处理程序或ProgressChanged事件处理程序中调用RunWorkerCompleted。您还使用代码ProgressBar.Value在DoWork中呼叫pbUpload.Value = 0。
此外，您应该从您的UI线程（即MessageBox.Show或ProgressChanged处理程序）中调用RunworkerCompleted，以便MessageBox可以与您的表单消息泵关联。您应该将表单对象传递给MessageBox.Show以将消息框与表单相关联，这样在显示消息框时就无法将表单带到前台。例如：
MessageBox.Show(this,
"There are files in this folder that are not .tiff. Please ensure only .tiff files are in this folder.",
"Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);
答案 1 :(得分：0)
在WinForms中，您只能访问创建控件的线程上的控件。您的DoWork事件处理程序未在创建表单的线程上运行（当然，这是重点）。因此，您不能访问DoWork处理程序中表单上的任何控件。这样做会产生不可预测的结果。
答案 2 :(得分：0)
我在完成后台进程后引发了与TargetInvocation Exception完全相同的问题。在backgroundWorker ProgressChanges事件中，我有对控件的引用，如下所示.private void m_oWorker_ProgressChanged（object sender，ProgressChangedEventArgs e） {
// This function fires on the UI thread so it's safe to edit
// the UI control directly, no funny business with Control.Invoke :)
CurrentState state =
(CurrentState)e.UserState;
txtProgress.Text = state.CrawlStatus;
lblStatus2.Text = state.sStatus;
txtItemsStored.Text = state.TotItems.ToString() + " items";
txtLastRunTime.Text = state.MostRecentGatherDate.ToString();
AppNameKey.SetValue("LastCrawlTime", txtLastRunTime.Text);
}`
DoWork事件从控件中读取
private void m_oWorker_DoWork(object sender, DoWorkEventArgs e)
{
DateTime LastCrawlTime;
try
{
LastCrawlTime = Convert.ToDateTime(txtLastRunTime.Text);
if (lblStatus2.Text != "Status: Running" || (!cmdRunNow.Enabled && cmdStopRun.Enabled)) // run is not currently running or cmdRunNow clicked
{
//lblStatus2.Text = "Status: Running";
GetUpdated(LastCrawlTime,e);
}
}
catch (Exception Ex)
{
MessageBox.Show(Ex.Message);
}
}
RunWorkedrCompleted事件写入控件：
void m_oWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Cancelled)
{
lblStatus2.Text = "Status: Stopped";
cmdStopRun.Enabled = false;
}
// Check to see if an error occurred in the background process.
else if (e.Error != null)
{
lblStatus2.Text = "Fatal Error while processing.";
}
else
{
// Everything completed normally.
//CurrentState state = (CurrentState)e.UserState;
lblStatus2.Text = "Status: Finished";
}
}
这些都没有造成问题。导致问题的原因是尝试在RunWorker_Completed事件中引用e.UserState（上面已注释掉）
答案 3 :(得分：-1)
我想出了这个问题。
进度条超出了允许的最大值（100）。
问题是在代码中，我正在增加进度条：
current = current + 2;
我将其替换为：
current++;
我加2的原因仅仅是为了测试目的。