dart compare datetime code example
Example: fluter check that date is greater than another date
var now = new DateTime.now();
var berlinWallFellDate = new DateTime.utc(1989, 11, 9);
// 0 denotes being equal positive value greater and negative value being less
if(berlinWallFellDate.compareTo(now)>0)
{
//peform logic here.....
}