将NSDate转换为Unix时间戳以在词典中使用

Question

While there are numerous examples on SO and the web of converting the current date to a unix timestamp, I can't seem to find one for any date.

This code produces error shown.

NSDate *date = self.datepicker.date;
time_t start = (time_t) [date timeIntervalSince1970];//collection element of time_t is not an objective-c object

Would appreciate any suggestions.

Answer 1

I believe that code will work and the error message relates to a different statement.

If you want to put that time_t into a dictionary then you'll need to wrap it in an NSNumber object. However you may as well keep it as an NSTimeInterval ( double ) and cast it when using it:

NSDate *date = self.datepicker.date;
NSTimeInterval start = [date timeIntervalSince1970]
dict[@"startTime"] = @(start);

However you can also cast it before adding it to the dictionary if you really want to.