winform 時間控件 能夠選擇時分 設置爲空

DateTimePicker.ShowUpDown = true;
DateTimePicker.CustomFormat = "hh:mm";
DateTimePicker.Format = System.Windows.Forms.DateTimePickerFormat.Custom;

設置爲空

dtp.Format = DateTimePickerFormat.Custom;
dtp.CustomFormat = " ";
dtp.Value = DateTime.FromOADate(0);
dtp.Text = string.Empty;