Oh, I recently killed whole day to make this working! So the solution is: Make your Image control free resources. So set the BitmapImage bitmapImage = image.Source as BitmapImage; bitmapImage.UriSource = null; image.Source = null; as it was mentioned before. Make sure you virtualize _bitmap on every item of the list. You should load it … Read more
It would be String MyStr = ListBox.items[5].ToString();
In Windows Forms, in a scenario that you want to see changes of data source in the bound list control, like ComboBox, ListBox or DataGridView (complex two-way data binding), you should use a class that implements IBindingList interface as DataSource of data binding. The most suitable implementation is BindingList<T>. This way each add/remove in the … Read more
Do you want to remove all items? If so, do the foreach first, then just use Items.Clear() to remove all of them afterwards. Otherwise, perhaps loop backwards by indexer: listBox1.BeginUpdate(); try { for(int i = listBox1.Items.Count – 1; i >= 0 ; i–) { // do with listBox1.Items[i] listBox1.Items.RemoveAt(i); } } finally { listBox1.EndUpdate(); }
To answer the overarching question – how to do this in WinForms – I’d suggest the following: Use a WPF ListBox in your WinForms application, wrapped in an ElementHost. This has its own issues, but I think it’s the cleanest way to get the desired effect. if that doesn’t fit the bill, then Use a … Read more
A format exception, according to the documentation means: value does not consist of an optional sign followed by a sequence of digits (0 through 9). Whatever you’re getting on this line: string test = listBox2.SelectedItem.ToString().Trim(); Is not an parse-able integer. You should debug to figure out what the value is that you’re actually getting. Hint: … Read more
SelectedIndices is what you want if you have enabled multi-select. You can also check the size of the SelectedItems property. The documentation for ListBox.SelectedIndex states: For a standard ListBox, you can use this property to determine the index of the item that is selected in the ListBox. If the SelectionMode property of the ListBox is … Read more