public void LendItem(string itemid, string lendby, string witnessBy)
{
var item = dac.GetItem(x => x._id == itemid);
item.Canlend = false;
item.CanSendBack = true;
var lenitem = dac.GetLendItem(x => x.ItemId == item._id);
LendLog newLog = new LendLog()
{
ActionBy = lendby,
ActionDate = DateTime.UtcNow,
Status = "lend",
WitnessBy = witnessBy,
};
var logs = lenitem.Log.ToList();
logs.Add(newLog);
lenitem.Log = logs;
dac.UpdateItem(item);
dac.UpdtaeLendItem(lenitem);
}