类型';System.InvalidCastException';发生

本文关键字:发生 InvalidCastException System 类型 | 更新日期: 2023-09-27 18:19:42

在我的类中,我为ListBoxItem编写了双击事件。当单击listBox的条目时,它应该只返回该特定条目。但在我的情况下,尽管我点击了一个条目,但所有条目都会返回,并出现"InvalidCastException"。那么,我应该如何更改才能获得单个条目。

这是双击事件代码:

private void ListBoxItem_DoubleClick(object sender, RoutedEventArgs e)
    {
        //Submit clicked Entry
        Harvest_TimeSheetEntry entryToPost = (Harvest_TimeSheetEntry)sender;
            if (!entryToPost.isSynced)
            {
                //Check if something is selected in selectedProjectItem For that item
             if (entryToPost.ProjectNameBinding == "Select Project")
                    MessageBox.Show("Please Select a Project for the Entry");
                else
                    Globals._globalController.harvestManager.postHarvestEntry(entryToPost);
            }
            else
            {
                //Already synced.. Make a noise or something
                MessageBox.Show("Already Synced;TODO Play a Sound Instead");
            }
    }
In xml:
<ListBox x:Name="listBox1" ItemsSource="{Binding}"  Margin="0,131,0,59" ItemTemplateSelector="{StaticResource templateSelector}" ListBoxItem.MouseDoubleClick="ListBoxItem_DoubleClick"/>

类型';System.InvalidCastException';发生

ListBox将其项隐式包装到ListBoxItem中。尝试将sender强制转换为ListBoxItem,然后获取其Content属性

在进一步处理

之前,尝试使用运算符而不是直接铸造,并包括null检查

最后,它成功了。

private void listBox1_MouseDoubleClick(object sender, MouseButtonEventArgs e)
    {
        //Submit clicked Entry
        try
        {
            ListBoxItem item = (ListBoxItem)sender;
            Harvest_TimeSheetEntry entryToPost = (Harvest_TimeSheetEntry)item.Content;
            if (!entryToPost.isSynced)
            {
                //Check if something is selected in selectedProjectItem For that item
                if (entryToPost.ProjectNameBinding == "Select Project")
                    MessageBox.Show("Please Select a Project for the Entry");
                else
                    Globals._globalController.harvestManager.postHarvestEntry(entryToPost);
            }
            else
            {
                //Already synced.. Make a noise or something
                MessageBox.Show("Already Synced;TODO Play a Sound Instead");
            }
        }
        catch (Exception)
        { }
     }