如何找到星期几的使用可可任何给定的日期(How to find what day of the we

我试图找出什么天（即周一，周五...）任何给定的日期（即2009年6月27日）

谢谢。

Answer 1:

我一直在做：

NSDateFormatter* theDateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[theDateFormatter setFormatterBehavior:NSDateFormatterBehavior10_4];
[theDateFormatter setDateFormat:@"EEEE"];
NSString *weekDay =  [theDateFormatter stringFromDate:[NSDate date]];

这有让你选择你想如何将返回的工作日（通过改变setDateFormat的日期格式字符串的好处：通话

很多的更多信息：

http://developer.apple.com/documentation/Cocoa/Conceptual/DataFormatting/Articles/dfDateFormatting10_4.html#//apple_ref/doc/uid/TP40002369

Answer 2:

你可以看看到的NSDate和NSCalendar类。 例如， 在这里和这里

它们提供了下面的代码：

NSDate *today = [NSDate date];
NSCalendar *gregorian = [[NSCalendar alloc]
                         initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *weekdayComponents =
                [gregorian components:(NSDayCalendarUnit | NSWeekdayCalendarUnit) fromDate:today];
NSInteger day = [weekdayComponents day];
NSInteger weekday = [weekdayComponents weekday];

Answer 3:

使用NSCalendar和NSDateComponents。 如图所示，NSDateComponents文档中：

NSCalendar *gregorian = [[NSCalendar alloc]
initWithCalendarIdentifier:NSGregorianCalendar];
NSDate *date = [gregorian dateFromComponents:comps];
NSDateComponents *weekdayComponents = [gregorian components:NSWeekdayCalendarUnit fromDate:date];
int weekday = [weekdayComponents weekday];

Answer 4:

下面是我结束了，该工程完全按照预期。 这需要时间，改变是在第一个月的日期，并获取日期的当天 ：

    NSDateComponents *components = [[NSCalendar currentCalendar] components:NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear fromDate:date];
NSDateComponents *monthDateComponents = [[NSCalendar currentCalendar] components: NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear |
                                         NSCalendarUnitHour | NSCalendarUnitMinute | NSCalendarUnitSecond fromDate: date];

//  build date as start of month
monthDateComponents.year = components.year;
monthDateComponents.month = components.month;
monthDateComponents.day = 1;

NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
//    [gregorian setFirstWeekday:1];

NSDate *builtDate =[gregorian dateFromComponents: monthDateComponents];
//    NSDateComponents *weekdayComponents =[gregorian components: NSCalendarUnitWeekday fromDate: builtDate];

NSDateFormatter *df = [NSDateFormatter new];
[df setDateFormat:@"E"];

NSString *firstDay = [df stringFromDate:builtDate];
if([firstDay isEqual:@"Sun"])  //  do for the other 6 days as appropriate
    return 7;

文章来源: How to find what day of the week for any given date using Cocoa