如何删除所有列表框项目？

Question

I created two RadioButton (Weight and Height). I will do switch between the two categories. But the they share the same ListBox Controllers (listBox1 and listBox2).

Is there any good method to clear all the ListBox items simpler? I didn't find the removeAll() for ListBox. I don't like my complex multi-lines style which I posted here.

private void Weight_Click(object sender, RoutedEventArgs e)
    {
        // switch between the radioButton "Weith" and "Height"
        // Clear all the items first
        listBox1.Items.Remove("foot"); 
        listBox1.Items.Remove("inch");
        listBox1.Items.Remove("meter");
        listBox2.Items.Remove("foot");
        listBox2.Items.Remove("inch");
        listBox2.Items.Remove("meter");

        // Add source units items for listBox1
        listBox1.Items.Add("kilogram");
        listBox1.Items.Add("pound");

        // Add target units items for listBox2
        listBox2.Items.Add("kilogram");
        listBox2.Items.Add("pound");
    }

    private void Height_Click(object sender, RoutedEventArgs e)
    {
        // switch between the radioButton "Weith" and "Height"
        // Clear all the items first
        listBox1.Items.Remove("kilogram");
        listBox1.Items.Remove("pound");
        listBox2.Items.Remove("kilogram");
        listBox2.Items.Remove("pound");

        // Add source units items for listBox1
        listBox1.Items.Add("foot");
        listBox1.Items.Add("inch");
        listBox1.Items.Add("meter");

        // Add target units items for listBox2
        listBox2.Items.Add("foot");
        listBox2.Items.Add("inch");
        listBox2.Items.Add("meter");
    }

Answer 1

和Winform 和Webform 的方式不一样吗？

listBox1.Items.Clear();

Answer 2

I think it would be better to actually bind your listBoxes to a datasource, since it looks like you are adding the same elements to each listbox. A simple example would be something like this:

    private List<String> _weight = new List<string>() { "kilogram", "pound" };
    private List<String> _height = new List<string>() { "foot", "inch", "meter" };

    public Window1()
    {            
        InitializeComponent();
    }        

    private void Weight_Click(object sender, RoutedEventArgs e)
    {
        listBox1.ItemsSource = _weight;
        listBox2.ItemsSource = _weight;
    }

    private void Height_Click(object sender, RoutedEventArgs e)
    {
        listBox1.ItemsSource = _height;
        listBox2.ItemsSource = _height;
    }

Answer 3

Write the following code in the .cs file:

ListBox.Items.Clear();

Answer 4

while (listBox1.Items.Count > 0){ 
    listBox1.Items.Remove(0);
}

Answer 5

您应该能够使用Clear()方法。

Answer 6

I made on this way, and work properly to me:

if (listview1.Items.Count > 0)
        {
            for (int a = listview1.Items.Count -1; a > 0 ; a--)
            {
                listview1.Items.RemoveAt(a);
            }
                listview1.Refresh();

        }

Explaining: using "Clear()" erases only the items, do not removes then from object, using RemoveAt() to removing an item of beginning position just realocate the others [if u remove item[0], item[1] turns into [0] triggering a new internal event], so removing from the ending no affect de others position, its a Stack behavior, this way we can Stack over all items, reseting the object.

Answer 7

• VB ListBox2.DataSource = Nothing
• C# ListBox2.DataSource = null;