从WinForm中的列表框中删除项目

Question

I am using VS2010, C#, .Net 4.0 and WinFormApplication.

I have a listbox which is populated from a datasource. I want to remove an item at a time when they are double clicked.

I read somewhere that if I populate my listbox from a datasource, no item can be removed. Is this true? If not, then how can I remove individual items?

I tried the following:

listbox1.Items.Remove(listbox1.SelectedIndex);

listbox1.Items.Remove(listbox1.SelectedIndex);

lbTableColumns.Items.Remove(lbTableColumns.SelectedItem);

which cause the following error:

ERROR: Items collection cannot be modified when the DataSource property is set.

Answer 1

When using a DataBinding you cannot remove items from the ListBox , just as the error states. What would happen if the object changes within the DataSource , but has been removed from the presentation?

If you are working with DataSources you need to remove the object from the DataSource itself. Try something like this:

IList<MyObj> myList = new List<MyObj>();

private void DataBind()
{
    myListBox.BeginUpdate();
    myListBox.DataSource = myList;
    myListBox.EndUpdate();
}

private void OnMyListBoxItemDoubleClicked(object sender, EventArgs e)
{
    myList.RemoveAt(myListBox.SelectedIndex);
    DataBind();
}