C# 用法总结 1

1 判断文本框中输入的IP地址是否合法

Regex reg = new Regex(@"(?n)^(([1-9]?[0-9]|1[0-9]{2}|2([0-4][0-9]|5[0-5]))/.){3}([1-9]?[0-9]|1[0-9]{2}|2([0-4][0-9]|5[0-5]))$");

if (reg.IsMatch(tb_IP.Text))

lb_IP.Items.Add(tb_IP.Text);

else

MessageBox.Show("It's not a variable IP!");

2 C＃删除listbox中选定的项

//确定消息头

string title = "Confirmation";

//确定消息正文

string text = "Are you sure,you want to delete selected filter value(s)?";

DialogResult m_dr = MessageBox.Show(text, title, MessageBoxButtons.YesNo);

if (m_dr==DialogResult.Yes)

{

lb_IP.Items.Remove(lb_IP.SelectedItem);

}