C＃ - 从列表框中删除所有项目

Question

I have a C# winform that uses a listbox with a bound list for the datasource. The list is created from a text file on the computer. I'm trying to create a "Remove all" button for this listbox and am having a little trouble.

First, here is the relevant code:

private void btnRemoveAll_Click(object sender, EventArgs e)
    {
        // Use a binding source to keep the listbox updated with all items
        // that we add
        BindingSource bindingSource = (BindingSource)listBox1.DataSource;

        // There doesn't seem to be a method for purging the entire source,
        // so going to try a workaround using the main list.
        List<string> copy_items = items;
        foreach (String item in copy_items)
        {
            bindingSource.Remove(item);
        }
    }

I've tried foreaching the bindingSource, but it gives an enumeration error and just won't work. As far as I can tell, there's not code to just purge an entire source, so I tried going through the List itself and removing them via the item name, but that doesn't work either since the foreach actually returns an object or something and not a string.

Any suggestions on how to do this?

Answer 1

您可以通过输入直接完成

listBox1.Items.Clear();

Answer 2

If you bound the Listbox to a BindingSource using some generic List then you can just do this:

BindingSource bindingSource = (BindingSource)listBox1.DataSource;
IList SourceList = (IList)bindingSource.List;

SourceList.Clear();

On the other handy, holding a reference to the underlaying List in your Form, Viewmodel or whatever would do the trick aswell.

EDIT: This only works if your List is a ObservableCollection. For normal List you can try call ResetBindings() on the BindingSource to enforce a refresh.