If you really are limited to one preposition I would use 'at', since the date & time as stated is precise to the minute. That requires 'at'. – WS2. Jul 7 '14 at ... ... <看更多>

You can create one with:- Date.prototype.addDays = function(days) { var date = new Date(this.valueOf()); date.setDate(date.getDate() + days); return date; } ... ... <看更多>