2019獨角獸企業重金招聘Python工程師標準>>>

1、在.h文件

#import <Foundation/Foundation.h>typedef enum{QHIntTypeRound = 0, //四舍五入QHIntTypeCeil = 1, //向上取值QHIntTypeFloor = 2, //向下取值 }QHIntType; @interface NSObject (timeStamp)+ (NSString *)timechange:(NSString *)timeStr withFormat:(NSString *)format;+ (NSString *)saveLength:(NSInteger)length andOldStr:(NSString *)str andType:(QHIntType)qhType; @end

2、在.m文件

#import "NSObject+timeStamp.h"@implementation NSObject (timeStamp)+ (NSString *)timechange:(NSString *)timeStr withFormat:(NSString *)format {if (timeStr.length>9) {NSTimeInterval time =[[timeStr substringToIndex:10] doubleValue];NSDate *detaildate=[NSDate dateWithTimeIntervalSince1970:time];//實例化一個NSDateFormatter對象NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];//設定時間格式,這里可以設置成自己需要的格式[dateFormatter setDateFormat:format];NSString *currentDateStr = [dateFormatter stringFromDate: detaildate];return currentDateStr;}else {NSTimeInterval time =[timeStr doubleValue];NSDate *detaildate=[NSDate dateWithTimeIntervalSince1970:time];//實例化一個NSDateFormatter對象NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];//設定時間格式,這里可以設置成自己需要的格式[dateFormatter setDateFormat:format];NSString *currentDateStr = [dateFormatter stringFromDate: detaildate];if (timeStr.length<1) {return @"";}return currentDateStr;// return QHLocalizedString(@"CurrencyExchangeCommissionNoNet", nil);}}+ (NSString *)saveLength:(NSInteger)length andOldStr:(NSString *)str andType:(QHIntType)qhType{if (!str) {return @"";}NSString *resultStr;NSArray *array = [str componentsSeparatedByString:@"."];if (array.count >1) {NSString *firstt = array[0];NSString *second = array[1];if (second.length > length) {NSRange range = {length,1};NSString *round = [second substringWithRange:range];NSString *newStr = [second substringToIndex:length];switch (qhType) {case QHIntTypeRound:{if ([round intValue]>length) {newStr = [NSString stringWithFormat:@"%@",@([newStr intValue]+1)];}}break;case QHIntTypeCeil:{newStr = [NSString stringWithFormat:@"%@",@([newStr intValue]+1)];}break;case QHIntTypeFloor:{}default:break;}resultStr = [NSString stringWithFormat:@"%@.%@",firstt,newStr];return resultStr ;}else{return str;}}else{return str;}}@end

3、說明：第一方法是將時間戳轉換成指定時間格式，第二方法是將傳入的數值保留指定小數后進行四舍五入、向上取值、向下取值等操作。

轉載于:https://my.oschina.net/u/2519763/blog/906622

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