调用线程不能访问这个对象，因为它属于另一个线程

我的代码如下

public CountryStandards()
{
    InitializeComponent();
    try
    {
        FillPageControls();
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message, "Country Standards", MessageBoxButton.OK, MessageBoxImage.Error);
    }
}

/// <summary>
/// Fills the page controls.
/// </summary>
private void FillPageControls()
{
    popUpProgressBar.IsOpen = true;
    lblProgress.Content = "Loading. Please wait...";
    progress.IsIndeterminate = true;
    worker = new BackgroundWorker();
    worker.DoWork += new System.ComponentModel.DoWorkEventHandler(worker_DoWork);
    worker.ProgressChanged += new System.ComponentModel.ProgressChangedEventHandler(worker_ProgressChanged);
    worker.WorkerReportsProgress = true;
    worker.WorkerSupportsCancellation = true;
    worker.RunWorkerCompleted += new System.ComponentModel.RunWorkerCompletedEventHandler(worker_RunWorkerCompleted);
    worker.RunWorkerAsync();                    
}

private void worker_DoWork(object sender, System.ComponentModel.DoWorkEventArgs e)
{
    GetGridData(null, 0); // filling grid
}

private void worker_ProgressChanged(object sender, System.ComponentModel.ProgressChangedEventArgs e)
{
    progress.Value = e.ProgressPercentage;
}

private void worker_RunWorkerCompleted(object sender, System.ComponentModel.RunWorkerCompletedEventArgs e)
{
    worker = null;
    popUpProgressBar.IsOpen = false;
    //filling Region dropdown
    Standards.UDMCountryStandards objUDMCountryStandards = new Standards.UDMCountryStandards();
    objUDMCountryStandards.Operation = "SELECT_REGION";
    DataSet dsRegionStandards = objStandardsBusinessLayer.GetCountryStandards(objUDMCountryStandards);
    if (!StandardsDefault.IsNullOrEmptyDataTable(dsRegionStandards, 0))
        StandardsDefault.FillComboBox(cmbRegion, dsRegionStandards.Tables[0], "Region", "RegionId");

    //filling Currency dropdown
    objUDMCountryStandards = new Standards.UDMCountryStandards();
    objUDMCountryStandards.Operation = "SELECT_CURRENCY";
    DataSet dsCurrencyStandards = objStandardsBusinessLayer.GetCountryStandards(objUDMCountryStandards);
    if (!StandardsDefault.IsNullOrEmptyDataTable(dsCurrencyStandards, 0))
        StandardsDefault.FillComboBox(cmbCurrency, dsCurrencyStandards.Tables[0], "CurrencyName", "CurrencyId");

    if (Users.UserRole != "Admin")
        btnSave.IsEnabled = false;

}

/// <summary>
/// Gets the grid data.
/// </summary>
/// <param name="sender">The sender.</param>
/// <param name="pageIndex">Index of the page.( used in case of paging)   </pamam>
private void GetGridData(object sender, int pageIndex)
{
    Standards.UDMCountryStandards objUDMCountryStandards = new Standards.UDMCountryStandards();
    objUDMCountryStandards.Operation = "SELECT";
    objUDMCountryStandards.Country = txtSearchCountry.Text.Trim() != string.Empty ? txtSearchCountry.Text : null;
    DataSet dsCountryStandards = objStandardsBusinessLayer.GetCountryStandards(objUDMCountryStandards);
    if (!StandardsDefault.IsNullOrEmptyDataTable(dsCountryStandards, 0) && (chkbxMarketsSearch.IsChecked == true || chkbxBudgetsSearch.IsChecked == true || chkbxProgramsSearch.IsChecked == true))
    {
        DataTable objDataTable = StandardsDefault.FilterDatatableForModules(dsCountryStandards.Tables[0], "Country", chkbxMarketsSearch, chkbxBudgetsSearch, chkbxProgramsSearch);
        dgCountryList.ItemsSource = objDataTable.DefaultView;
    }
    else
    {
        MessageBox.Show("No Records Found", "Country Standards", MessageBoxButton.OK, MessageBoxImage.Information);
        btnClear_Click(null, null);
    }
}

该步骤遵循judmcountrystandards。Country = txtSearchCountry.Text.Trim() !=字符串。空的吗?txtSearchCountry。文本:null;在获取网格数据时抛出异常

调用线程不能访问此对象，因为有不同的线程拥有它。

这里出了什么问题?

当前回答

根据您的需要，肯定有不同的方法来做到这一点。

我使用UI更新线程(它不是主UI线程)的一种方法是让线程开始一个循环，其中整个逻辑处理循环被调用到UI线程上。

例子:

public SomeFunction()
{
    bool working = true;
    Thread t = new Thread(() =>
    {
        // Don't put the working bool in here, otherwise it will 
        // belong to the new thread and not the main UI thread.
        while (working)
        {
            Application.Current.Dispatcher.Invoke(() =>
            {
                // Put your entire logic code in here.
                // All of this code will process on the main UI thread because
                //  of the Invoke.
                // By doing it this way, you don't have to worry about Invoking individual
                //  elements as they are needed.
            });
        }
    });
}

这样，代码就完全在主UI线程上执行。对于那些难以理解跨线程操作的业余程序员来说，这可能是一种专业方法。然而，对于更复杂的ui(特别是在执行动画时)，它很容易成为一个骗局。实际上，这只是为了伪造一个更新UI的系统，然后返回来处理任何已经触发的事件，以代替有效的跨线程操作。

2020-07-14 02:05:31

其他回答

这对我很有用。

new Thread(() =>
        {

        Thread.CurrentThread.IsBackground = false;
        Application.Current.Dispatcher.BeginInvoke(DispatcherPriority.Background, (SendOrPostCallback)delegate {

          //Your Code here.

        }, null);
        }).Start();

2018-06-15 15:41:52

我在从WPF控件中选择的第二个项目上奇怪地遇到了这个错误。

原因是我将数据加载到RX SourceCache中，加载的元素将observablecollection作为导航属性包装到CollectionView中。observablecollection连接到UIThread，数据由WorkerThread加载。由于CollectionView只在显示第一个元素时被填充，不同线程的问题只发生在被选择的第二个项目上。

解决方案是将子列表作为ReadOnlyObservableCollections移动到ViewModel中，并根据当前选择的主元素筛选子元素表的完整列表。

2022-09-02 14:51:28

你需要在UI线程上做。使用:

Dispatcher.BeginInvoke(new Action(() => {GetGridData(null, 0)}));

2013-03-05 11:27:36

这是人们刚开始时遇到的一个普遍问题。每当你从主线程以外的线程更新UI元素时，你需要使用:

this.Dispatcher.Invoke(() =>
{
    ...// your code here.
});

你也可以使用control. dispatcher . checkaccess()来检查当前线程是否拥有该控件。如果它确实拥有它，那么您的代码看起来就正常。否则，使用上述图案。

2012-03-16 06:22:58

根据您的需要，肯定有不同的方法来做到这一点。

我使用UI更新线程(它不是主UI线程)的一种方法是让线程开始一个循环，其中整个逻辑处理循环被调用到UI线程上。

例子:

public SomeFunction()
{
    bool working = true;
    Thread t = new Thread(() =>
    {
        // Don't put the working bool in here, otherwise it will 
        // belong to the new thread and not the main UI thread.
        while (working)
        {
            Application.Current.Dispatcher.Invoke(() =>
            {
                // Put your entire logic code in here.
                // All of this code will process on the main UI thread because
                //  of the Invoke.
                // By doing it this way, you don't have to worry about Invoking individual
                //  elements as they are needed.
            });
        }
    });
}

2020-07-14 02:05:31

调用线程不能访问这个对象，因为它属于另一个线程

推荐文章

最新文章

标签