private void listView1_DoubleClick(object sender, EventArgs e)
{
if (MessageBox.Show("还书", "确认是否还书", MessageBoxButtons.YesNo) == DialogResult.Yes)
{
if (listView1.SelectedItems.Count == 1)
{
string logid = listView1.SelectedItems[0].SubItems[3].Text;
BookAPI.ReturnBook(Program.users, logid);
LoadData();
}
}
}