ios - Check date format style in Objective-C -

how can check date in format getting response api , in getting dates converting date string according format confusion getting date in 2 format, yyyy-mm-dd't'hh:mm:ss.sss , yyyy-mm-dd't'hh:mm:ss include sss , not, kindly tell me how can first check date format style , use date format according that.

here following using code converting string desired format.

nsstring *datestr = @"2016-01-18t13:28:06.357"; nsdateformatter *formatter = [[nsdateformatter alloc] init]; [formatter setdateformat:@"yyyy-mm-dd't'hh:mm:ss.sss"]; nsdate *date = [formatter datefromstring:datestr]; 

looking response.

initially check like

nsdate *date; nsdateformatter *formatter = [[nsdateformatter alloc] init];  // check   2016-01-18t13:28:06.357 [formatter setdateformat:@"yyyy-mm-dd't'hh:mm:ss.sss"]; // returns date ,  date = [formatter datefromstring:datestr];  // check if date empty or   if(date == nil) {   // add date format    [formatter setdateformat:@"yyyy-mm-dd't'hh:mm:ss"];   date = [formatter datefromstring:datestr]; }