列表框中点击空白地方不选中项

Question

listBox1里面有几个项，我选中其中一项，当我单击列表框的空白地方时，如何不选中任何项？
private void listBox1_Click(object sender,EventArgs e)
{}还有 点击空白的地方时，ListBoxs.SelectedIndex等于多少？

Answer 1

ListBoxs.SetSelect(ListBoxs.Items.Count-1,false);给分啊 private void listBox_FenLei_MouseDown(object sender, MouseEventArgs e)
        {
                if (this.listBox_FenLei.SelectedItem != null)
                {
                    //此句可防止双击空白处出现错误的问题                     indexofsource = ((ListBox)sender).IndexFromPoint(e.X, e.Y);
                  
                     if (indexofsource == ListBox.NoMatches)    //如果点的是空白
                      {
                          if (this.listBox_FenLei.Items.Count != 0)
                        {
                            this.listBox_FenLei.SetSelected(this.listBox_FenLei.Items.Count - 1, false);
                        }                    }
                                    
                }