IOS基础：常用的Foundation分类方法

2020-11-03 本文已影响0人时光啊混蛋_97boy

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一、NSDate

获取当前的时间

a、运行效果

2020-11-03 17:19:56.771598+0800 CategoryNSDemo[3514:4320468] 2020年，11月，3日，17时，19分，56秒，weekday为3

b、功能代码

- (NSCalendar *)calendar
{
    return [NSCalendar calendarWithIdentifier:NSCalendarIdentifierGregorian];
}

- (NSInteger)year
{
    return [[[self calendar] components:NSCalendarUnitYear fromDate:self] year];
}

- (NSInteger)month
{
    return [[[self calendar] components:NSCalendarUnitMonth fromDate:self] month];
}

- (NSInteger)day
{
    return [[[self calendar] components:NSCalendarUnitDay fromDate:self] day];
}

- (NSInteger)hour
{
    return [[[self calendar] components:NSCalendarUnitHour fromDate:self] hour];
}

- (NSInteger)minute
{
    return [[[self calendar] components:NSCalendarUnitMinute fromDate:self] minute];
}

- (NSInteger)second
{
    return [[[self calendar] components:NSCalendarUnitSecond fromDate:self] second];
}

- (NSInteger)weekday
{
    return [[[self calendar] components:NSCalendarUnitWeekday fromDate:self] weekday];
}

c、调用方式

- (void)getCurrentTime
{
    NSDate *date = [NSDate date];
    NSLog(@"%ld年，%ld月，%ld日，%ld时，%ld分，%ld秒，周%ld",(long)date.year,date.month,date.day,date.hour,date.minute,date.second,date.weekday);
}

获取星期几

a、运行效果

2020-11-03 17:30:10.725025+0800 CategoryNSDemo[3704:4330330] 星期二，周二，Tuesday

b、功能代码

- (NSString *)dayFromWeekday
{
    return [NSDate dayFromWeekday:self];
}

- (NSString *)dayFromWeekday2
{
    return [NSDate dayFromWeekday2:self];
}

- (NSString *)dayFromWeekday3
{
    return [NSDate dayFromWeekday3:self];
}

+ (NSString *)dayFromWeekday:(NSDate *)date
{
    switch([date weekday])
    {
        case 1:
            return @"星期天";
            break;
        case 2:
            return @"星期一";
            break;
        case 3:
            return @"星期二";
            break;
        case 4:
            return @"星期三";
            break;
        case 5:
            return @"星期四";
            break;
        case 6:
            return @"星期五";
            break;
        case 7:
            return @"星期六";
            break;
        default:
            break;
    }
    return @"";
}

c、调用方式

- (void)getWeekday
{
    NSDate *date = [NSDate date];
    NSLog(@"%@，%@，%@",[date dayFromWeekday],[date dayFromWeekday2],[date dayFromWeekday3]);
}

获取时间戳

a、运行效果

2020-11-03 18:07:06.473829+0800 CategoryNSDemo[4306:4359508] 获取当前时间戳字符串：1604398026
2020-11-03 18:07:06.474130+0800 CategoryNSDemo[4306:4359508] 获取当前系统时间的时间戳 [北京时间]：1604398026
2020-11-03 18:07:06.474209+0800 CategoryNSDemo[4306:4359508] 将date转换成时间戳 (NSDate => Timestamp)：1604398026
2020-11-03 18:07:06.474953+0800 CategoryNSDemo[4306:4359508] 将时间戳转换成date (Timestamp => NSDate)：2020-11-03 09:38:55 +0000
2020-11-03 18:07:06.476334+0800 CategoryNSDemo[4306:4359508] 将时间字符串转换成时间戳 (TimeString => Timestamp) [北京时间]：1605425940
2020-11-03 18:07:06.476510+0800 CategoryNSDemo[4306:4359508] 将时间戳转换成时间字符串 (Timestamp => TimeString) [北京时间]：2020-11-03 17:38

b、功能代码

获取当前时间戳字符串

+ (NSString *)currentTimeInterval
{
    NSDate *date = [NSDate date];
    NSTimeInterval timeInterval = [date timeIntervalSince1970];
    NSString *timeIntervalString = [NSString stringWithFormat:@"%d", (int)timeInterval];
    return timeIntervalString;
}

获取当前系统时间的时间戳 [北京时间]

+ (NSInteger)getNowTimestampWithFormatter:(NSString *)format
{
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateStyle:NSDateFormatterMediumStyle];
    [formatter setTimeStyle:NSDateFormatterShortStyle];
    [formatter setDateFormat:format];
    
    NSTimeZone *timeZone = [NSTimeZone timeZoneWithName:@"Asia/Beijing"];
    [formatter setTimeZone:timeZone];
    
    return [self timestampFromDate:[NSDate date]];
}

将date转换成时间戳 (NSDate => Timestamp)

+ (NSInteger)timestampFromDate:(NSDate *)date
{
    return [[NSNumber numberWithDouble:[date timeIntervalSince1970]] integerValue];
}

将时间戳转换成date (Timestamp => NSDate)

+ (NSDate *)dateFromTimestamp:(NSInteger)timestamp
{
    return [NSDate dateWithTimeIntervalSince1970:timestamp];
}

将时间字符串转换成时间戳 (TimeString => Timestamp) [北京时间]

+ (NSInteger)timestampFromTimeString:(NSString *)timeString formatter:(NSString *)format
{
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateStyle:NSDateFormatterMediumStyle];
    [formatter setTimeStyle:NSDateFormatterShortStyle];
    [formatter setDateFormat:format];
    
    NSTimeZone *timeZone = [NSTimeZone timeZoneWithName:@"Asia/Beijing"];
    [formatter setTimeZone:timeZone];
    
    // 将字符串按formatter转成NSDate
    NSDate *date = [formatter dateFromString:timeString];
    return [self timestampFromDate:date];
}

将时间戳转换成时间字符串 (Timestamp => TimeString) [北京时间]

+ (NSString *)timeStringFromTimestamp:(NSInteger)timestamp formatter:(NSString *)format
{
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateStyle:NSDateFormatterMediumStyle];
    [formatter setTimeStyle:NSDateFormatterShortStyle];
    [formatter setDateFormat:format];
    
    NSTimeZone *timeZone = [NSTimeZone timeZoneWithName:@"Asia/Beijing"];
    [formatter setTimeZone:timeZone];
    
    NSDate *timeDate = [self dateFromTimestamp:timestamp];
    return [formatter stringFromDate:timeDate];
}

c、调用方式

- (void)getTimeInterval
{
    NSLog(@"获取当前时间戳字符串：%@",[NSDate currentTimeInterval]);
    NSLog(@"获取当前系统时间的时间戳 [北京时间]：%ld",(long)[NSDate getNowTimestampWithFormatter:@"yyyy-MM-dd HH:mm"]);
    NSLog(@"将date转换成时间戳 (NSDate => Timestamp)：%ld",(long)[NSDate timestampFromDate:[NSDate date]]);
    NSLog(@"将时间戳转换成date (Timestamp => NSDate)：%@",[NSDate dateFromTimestamp:1604396335]);
    NSLog(@"将时间字符串转换成时间戳 (TimeString => Timestamp) [北京时间]：%ld",(long)[NSDate timestampFromTimeString:@"2020-11-15 15:39" formatter:@"yyyy-MM-dd HH:mm"]);
    NSLog(@"将时间戳转换成时间字符串 (Timestamp => TimeString) [北京时间]：%@",[NSDate timeStringFromTimestamp:1604396335 formatter:@"yyyy-MM-dd HH:mm"]);
}

时间字符串

a、运行效果

2020-11-03 18:20:22.327078+0800 CategoryNSDemo[4498:4368943] 将date转换成时间字符串 (NSDate => TimeString)：2020/11/03
2020-11-03 18:20:22.328636+0800 CategoryNSDemo[4498:4368943] 将时间字符串转换成date (TimeString ==> NSDate)：2020-11-14 16:00:00 +0000

b、功能代码

将date转换成时间字符串 (NSDate => TimeString)

+ (NSString *)stringWithDate:(NSDate *)date format:(NSString *)format
{
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:format];
    [formatter setLocale:[NSLocale currentLocale]];
    NSString *dateString = [formatter stringFromDate:date];
    return dateString;
}

将时间字符串转换成date (TimeString ==> NSDate)

+ (NSDate *)dateWithString:(NSString *)dateString format:(NSString *)format
{
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:format];
    return [formatter dateFromString:dateString];
}

c、调用方式

- (void)getTimeString
{
    NSLog(@"将date转换成时间字符串 (NSDate => TimeString)：%@",[NSDate stringWithDate:[NSDate date] format:@"yyyy/MM/dd"]);
    NSLog(@"将时间字符串转换成date (TimeString ==> NSDate)：%@",[NSDate dateWithString:@"2020-11-15" format:@"yyyy/MM/dd"]);
}

获取某个月的天数

a、运行效果

2020-11-03 18:27:05.649597+0800 CategoryNSDemo[4622:4374377] 获取2020年11月的天数：30

b、功能代码

+ (NSInteger)getSumOfDaysMonth:(NSInteger)month inYear:(NSInteger)year
{
    NSDateFormatter * formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:@"yyyy-MM"];
    NSString *dateString = [NSString stringWithFormat:@"%lu-%lu", year, month];
    NSDate *date = [formatter dateFromString:dateString];
    
    NSRange range = [[NSCalendar calendarWithIdentifier:NSCalendarIdentifierGregorian] rangeOfUnit:NSCalendarUnitDay inUnit:NSCalendarUnitMonth forDate:date];
    return range.length;
}

c、调用方式

- (void)getMonthDays
{
    NSLog(@"获取2020年11月的天数：%ld",(long)[NSDate getSumOfDaysMonth:11 inYear:2020]);
}

获取当前的"年月日时分"

a、运行效果

2020-11-03 18:29:51.024183+0800 CategoryNSDemo[4669:4377704] 获取当前的年月日时分：(
    2020,
    11,
    03,
    18,
    29
)

b、功能代码

+ (NSArray<NSString *> *)getCurrentTimeComponents
{
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:@"yyyy-MM-dd-HH-mm"];
    NSDate *date = [NSDate date];
    NSString *time = [formatter stringFromDate:date];
    return [time componentsSeparatedByString:@"-"];
}

c、调用方式

- (void)getTimeComponents
{
    NSLog(@"获取当前的年月日时分：%@",[NSDate getCurrentTimeComponents]);
}

比较日期

a、运行效果

2020-11-04 09:46:58.114920+0800 CategoryNSDemo[6325:4445550] 比较的结果为：-1
2020-11-04 09:46:58.115157+0800 CategoryNSDemo[6325:4445550] 2020-11-15日大于当前时间，属于未来

b、功能代码

比较两个date的大小关系

+ (NSComparisonResult)compareDateString1:(NSString *)dateString1
                             dateString2:(NSString *)dateString2
                               formatter:(NSString *)format
{
    NSDateFormatter *formatter = [[NSDateFormatter alloc]init];
    [formatter setDateFormat:format];
    
    NSDate *date1 = [[NSDate alloc] init];
    NSDate *date2 = [[NSDate alloc] init];
    
    date1 = [formatter dateFromString:dateString1];
    date2 = [formatter dateFromString:dateString2];
    
    return [date1 compare:date2];
}

是否小于当前时间(过去时间)

- (BOOL)isInPast
{
    return ([self compare:[NSDate date]] == NSOrderedAscending);
}

是否大于当前时间(未来时间)

- (BOOL)isInFuture
{
    return ([self compare:[NSDate date]] == NSOrderedDescending);
}

是否是今天

- (BOOL)isToday
{
    return [self isSameDay:[NSDate date]];
}

是否是同一天

- (BOOL)isSameDay:(NSDate *)anotherDate
{
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *components1 = [calendar components:(NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay) fromDate:self];
    NSDateComponents *components2 = [calendar components:(NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay) fromDate:anotherDate];
    
    return ([components1 year] == [components2 year] && [components1 month] == [components2 month] && [components1 day] == [components2 day]);
}

c、调用方式

- (void)compareDay
{
    NSComparisonResult result = [NSDate compareDateString1:@"2020-11-15" dateString2:@"2020-11-17" formatter:@"yyyy-MM-dd"];
    NSLog(@"比较的结果为：%ld",(long)result);
    
    NSDate *date = [NSDate dateWithString:@"2020-11-15" format:@"yyyy-MM-dd"];
    if ([date isInPast])
    {
        NSLog(@"2020-11-15日小于当前时间，属于过去");
    }
    
    if ([date isInFuture])
    {
        NSLog(@"2020-11-15日大于当前时间，属于未来");
    }
    
    if ([date isToday])
    {
        NSLog(@"2020-11-15日就在今天");
    }
}

计算日期

a、运行效果

2020-11-04 10:00:15.274302+0800 CategoryNSDemo[6532:4455232] 获取2天后的时间: 2020-11-06 02:00:15 +0000
2020-11-04 10:00:15.274430+0800 CategoryNSDemo[6532:4455232] 获取5天前的时间: 2020-10-30 02:00:15 +0000

b、功能代码

获取之前的日期时间

+ (NSDate *)backward:(NSInteger)backward unitType:(NSCalendarUnit)unit
{
    NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
    [dateComponents setValue:backward forComponent:unit];
    
    NSCalendar *calendar = [[self alloc] calendar];
    NSDate *dateFromDateComponents =  [calendar dateByAddingComponents:dateComponents toDate:[NSDate date] options:0];
    return dateFromDateComponents;
}

获取未来的日期时间

+ (NSDate *)forward:(NSInteger)forward unitType:(NSCalendarUnit)unit
{
    return [self backward:-forward unitType:unit];
}

c、调用方式

- (void)calculateDay
{
    NSLog(@"获取2天后的时间: %@",[NSDate backward:2 unitType:NSCalendarUnitDay]);
    NSLog(@"获取5天前的时间: %@",[NSDate forward:5 unitType:NSCalendarUnitDay]);
}

二、NSObject

AssociatedObject

a、运行效果

2020-11-04 10:25:56.441234+0800 CategoryNSDemo[7132:4474099] 被关联的值为: 97Boy

b、功能代码

- (id)getAssociatedValueForKey:(void *)key
{
    return objc_getAssociatedObject(self, key);
}

- (void)setAssociatedValue:(id)value withKey:(void *)key
{
    objc_setAssociatedObject(self, key, value, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (void)removeAssociatedObjects
{
    objc_removeAssociatedObjects(self);
}

// ASSIGN
- (void)setAssignValue:(id)value withKey:(SEL)key
{
    objc_setAssociatedObject(self, key, value, OBJC_ASSOCIATION_ASSIGN);
}

// COPY
- (void)setCopyValue:(id)value withKey:(SEL)key
{
    objc_setAssociatedObject(self, key, value, OBJC_ASSOCIATION_COPY_NONATOMIC);
}

c、调用方式

- (void)associatedObject
{
    NSArray *object = [[NSArray alloc] initWithObjects:@"Xie", @"Jia",@"Pei",nil];
    NSString *value = [[NSString alloc] initWithFormat:@"%@",@"97Boy"];
    
    [object setAssociatedValue:value withKey:&valueKey];
    
    NSString *associatedValue = (NSString *)[object getAssociatedValueForKey:&valueKey];
    NSLog(@"被关联的值为: %@", associatedValue);
}

三、NSNumber

金额浮点数高精度运算

a、运行效果

2020-11-25 18:26:25.587596+0800 CategoryNSDemo[82059:5281646] 金额浮点数高精度减法运算，默认两位小数处理:4.030000
2020-11-25 18:26:25.587701+0800 CategoryNSDemo[82059:5281646] 金额浮点数高精度比较，默认两位小数处理

b、功能代码

金额浮点数高精度减法运算，默认两位小数处理

- (double)minusDecimalNumber:(NSNumber *)subtrahendNum
{
    NSDecimalNumber *minuend = [self decimalNumber:self];
    NSDecimalNumber *subtrahend = [self decimalNumber:subtrahendNum];
    NSDecimalNumberHandler *handler = [[NSDecimalNumberHandler alloc] initWithRoundingMode:(NSRoundPlain) scale:2 raiseOnExactness:NO raiseOnOverflow:NO raiseOnUnderflow:NO raiseOnDivideByZero:YES];
    NSDecimalNumber *res = [minuend decimalNumberBySubtracting:subtrahend withBehavior:handler];
    return res.doubleValue;
}

金额浮点数高精度比较，默认两位小数处理

- (NSComparisonResult)compareDecimalNumber:(NSNumber *)num
{
    NSDecimalNumber *first = [self decimalNumber:self];
    NSDecimalNumber *last = [self decimalNumber:num];
    return [first compare:last];
}

将NSNumber转化为NSDecimalNumber

- (NSDecimalNumber *)decimalNumber:(NSNumber *)num
{
    NSDecimalNumber *decimalNumber = [NSDecimalNumber decimalNumberWithString:[NSString stringWithFormat:@"%.2f",num.doubleValue]];
    return decimalNumber;
}

c、调用方式

- (void)viewDidLoad
{
    [super viewDidLoad];
    
    NSNumber *firstNumber = @(7.1243545);
    NSNumber *secondNumber = @(3.093543325665);
    double result = [firstNumber minusDecimalNumber:secondNumber];
    NSLog(@"金额浮点数高精度减法运算，默认两位小数处理:%f",result);
    
    if ([firstNumber compareDecimalNumber:secondNumber])
    {
        NSLog(@"金额浮点数高精度比较，默认两位小数处理");
    }
}

Pod库

XJPCategoryKit可通过CocoaPods获得。要安装它，只需在Podfile中添加以下行：

pod 'XJPCategoryKit'

Demo

Demo在我的Github上，欢迎下载。
FunctionCodeBlock

IOS基础：常用的Foundation分类方法

目录

一、NSDate

获取当前的时间

a、运行效果

b、功能代码

c、调用方式

获取星期几

a、运行效果

b、功能代码

c、调用方式

获取时间戳

a、运行效果

b、功能代码

c、调用方式

时间字符串

a、运行效果

b、功能代码

c、调用方式

获取某个月的天数

a、运行效果

b、功能代码

c、调用方式

获取当前的"年月日时分"

a、运行效果

b、功能代码

c、调用方式

比较日期

a、运行效果

b、功能代码

c、调用方式

计算日期

a、运行效果

b、功能代码

c、调用方式

二、NSObject

AssociatedObject

a、运行效果

b、功能代码

c、调用方式

三、NSNumber

金额浮点数高精度运算

a、运行效果

b、功能代码

c、调用方式

Pod库

Demo

参考文献

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