public void TextBlockChange(TextBlock t, BookItem Bookitem)
{
/*"due_date": "2014-11-17",
"author": "徐森林，薛春华编著",
"barcode": "2296308",
"render_date": "2014-10-18",
"place": "中文图书阅览室（3）",
"title": "实变函数论",
"renew_time": "0"
*/
t.Text += "书名： " + Bookitem.title + "\n";
t.Text += "归还时间： " + Bookitem.due_date + "\n";
t.Text += "作者： " + Bookitem.author + "\n";
t.Text += "条码号： " + Bookitem.barcode + "\n";
t.Text += "借阅时间： " + Bookitem.render_date + "\n";
t.Text += "馆藏地： " + Bookitem.place + "\n";
t.Text += "续借次数： " + Bookitem.renew_time + "\n";
//t.Tapped += ReNewTap;
}
public async void ReNewTap(object sender, TappedRoutedEventArgs e)