1:原文摘自:http://mkhgg.blog.51cto.com/1741572/554134
1. stringWithFormat 用法:
[NSString stringWithFormat:
@"
Hight: %d°%@ Low: %d°%@
"
, [Temp],
@"
C
"
,[lTemp],
@"
C
"
];
NSString to NSData:
NSString* str= @"kilonet";
NSData* data=[str dataUsingEncoding:NSUTF8StringEncoding];
2. NSDate 用法:
NSDate
*
today;
NSDate
*
tomorrow;
today
=
[NSDate date];
tomorrow
=
[NSDate dateWithTimeInterval:(i
*
24
*
60
*
60
) sinceDate:today];
//
可能有更好的
Date format用法:
-(NSString *) getDay:(NSDate *) d {
NSString
*
s ;
NSDateFormatter
*
format
=
[[NSDateFormatter alloc] init];
[format setDateFormat:
@"
YYYY/MM/dd hh:mm:ss
"
];
s
=
[format stringFromDate:d];
[format release];
return
s;
}
各地时区获取:
代码
NSDate
*
nowDate
=
[NSDate
new
];
NSDateFormatter
*
formatter
=
[[NSDateFormatter alloc] init];
[formatter setDateFormat:
@"
yyyy/MM/dd HH:mm:ss
"
];
//
根据时区名字获取当前时间,如果该时区不存在,默认获取系统当前时区的时间
//
NSTimeZone* timeZone = [NSTimeZone timeZoneWithName:@"Europe/Andorra"];
//
[formatter setTimeZone:timeZone];
//
获取所有的时区名字
NSArray
*
array
=
[NSTimeZone knownTimeZoneNames];
//
NSLog(@"array:%@",array);
//
for循环
//
for(int i=0;i<[array count];i++)
//
{
//
NSTimeZone* timeZone = [NSTimeZone timeZoneWithName:[array objectAtIndex:i]];
//
[formatter setTimeZone:timeZone];
//
NSString *locationTime = [formatter stringFromDate:nowDate];
//
NSLog(@"时区名字:%@ : 时区当前时间: %@",[array objectAtIndex:i],locationTime);
//
//
NSLog(@"timezone name is:%@",[array objectAtIndex:i]);
//
}
//
快速枚举法
for
(NSString
*
timeZoneName
in
array){
[formatter setTimeZone:[NSTimeZone timeZoneWithName:timeZoneName]];
NSLog(
@"
%@,%@
"
,timeZoneName,[formatter stringFromDate:nowDate]);
}
[formatter release];
[nowDate release];
获取毫秒时间:
代码
NSDateFormatter
*
dateFormatter
=
[[NSDateFormatter alloc] init];
[dateFormatter setDateStyle:NSDateFormatterMediumStyle];
[dateFormatter setTimeStyle:NSDateFormatterShortStyle];
//
[dateFormatter setDateFormat:@"hh:mm:ss"]
[dateFormatter setDateFormat:
@"
yyyy-MM-dd HH:mm:ss.SSS
"
];
NSLog(
@"
Date%@
"
, [dateFormatter stringFromDate:[NSDate date]]);
[dateFormatter release];
3.
NSCalendar用法:
-(NSString *) getWeek:(NSDate *) d {
NSCalendar
*
calendar
=
[[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
unsigned units
=
NSYearCalendarUnit
|
NSMonthCalendarUnit
|
NSDayCalendarUnit
|
NSWeekdayCalendarUnit;
NSDateComponents
*
components
=
[calendar components:units fromDate:d];
[calendar release];
switch
([components weekday]) {
case
2
:
return
@"
Monday
"
;
break
;
case
3
:
return
@"
Tuesday
"
;
break
;
case
4
:
return
@"
Wednesday
"
;
break
;
case
5
:
return
@"
Thursday
"
;
break
;
case
6
:
return
@"
Friday
"
;
break
;
case
7
:
return
@"
Saturday
"
;
break
;
case
1
:
return
@"
Sunday
"
;
break
;
default
:
return
@"
No Week
"
;
break
;
}
//
用components,我们可以读取其他更多的数据。
}
4. 用Get方式读取网络数据:
//
将网络数读取为字符串
-
(NSString
*
) getDataByURL:(NSString
*
) url {
return
[[NSString alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:[url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]] encoding:NSUTF8StringEncoding];
}
//
读取网络图片
-
(UIImage
*
) getImageByURL:(NSString
*
) url {
return
[[UIImage alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:[url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]]];
}
5. 多线程NSThread用法 :
[NSThread detachNewThreadSelector:@selector(scheduleTask) toTarget:self withObject:nil];
-
(
void
) scheduleTask {
//
create a pool
NSAutoreleasePool
*
pool
=
[[NSAutoreleasePool alloc] init];
//
release the pool;
[pool release];
}
//
如果有参数,则这么使用:
[NSThread detachNewThreadSelector:@selector(scheduleTask:) toTarget:self withObject:[NSDate date]];
-
(
void
) scheduleTask:(NSDate
*
) mdate {
//
create a pool
NSAutoreleasePool
*
pool
=
[[NSAutoreleasePool alloc] init];
//
release the pool;
[pool release];
}
//
注意selector里有冒号。
//在线程里运行主线程里的方法
[self performSelectorOnMainThread:@selector(moveToMain) withObject:nil waitUntilDone:FALSE];
6. 定时器NSTimer用法:
代码
//
一个可以自动关闭的Alert窗口
UIAlertView
*
alert
=
[[UIAlertView alloc] initWithTitle:nil
message:[
@"
一个可以自动关闭的Alert窗口
"
delegate
:nil
cancelButtonTitle:nil
//
NSLocalizedString(@"OK", @"OK")
//
取消任何按钮
otherButtonTitles:nil];
//
[alert setBounds:CGRectMake(alert.bounds.origin.x, alert.bounds.origin.y, alert.bounds.size.width, alert.bounds.size.height+30.0)];
[alert show];
UIActivityIndicatorView
*
indicator
=
[[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
//
Adjust the indicator so it is up a few pixels from the bottom of the alert
indicator.center
=
CGPointMake(alert.bounds.size.width
/
2
, alert.bounds.size.height
-
40.0
);
[indicator startAnimating];
[alert insertSubview:indicator atIndex:
0
];
[indicator release];
[NSTimer scheduledTimerWithTimeInterval:
3.0f
target:self
selector:@selector(dismissAlert:)
userInfo:[NSDictionary dictionaryWithObjectsAndKeys:alert,
@"
alert
"
,
@"
testing
"
,
@"
key
"
,nil]
//
如果不用传递参数,那么可以将此项设置为nil.
repeats:NO];
NSLog(
@"
release alert
"
);
[alert release];
-
(
void
) dismissAlert:(NSTimer
*
)timer{
NSLog(
@"
release timer
"
);
NSLog([[timer userInfo] objectForKey:
@"
key
"
]);
UIAlertView
*
alert
=
[[timer userInfo] objectForKey:
@"
alert
"
];
[alert dismissWithClickedButtonIndex:
0
animated:YES];
}
定时器停止使用:
[timer invalidate];
timer
=
nil;
7. 用户缺省值NSUserDefaults读取:
//
得到用户缺省值
NSUserDefaults
*
defs
=
[NSUserDefaults standardUserDefaults];
//
在缺省值中找到AppleLanguages, 返回值是一个数组
NSArray
*
languages
=
[defs objectForKey:
@"
AppleLanguages
"
];
NSLog(
@"
all language语言 is %@
"
, languages);
//
在得到的数组中的第一个项就是用户的首选语言了
NSLog(
@"
首选语言 is %@
"
,[languages objectAtIndex:
0
]);
//
get the language & country code
NSLocale
*
currentLocale
=
[NSLocale currentLocale];
NSLog(
@"
Language Code is %@
"
, [currentLocale objectForKey:NSLocaleLanguageCode]);
NSLog(
@"
Country Code is %@
"
, [currentLocale objectForKey:NSLocaleCountryCode]);
8. View之间切换的动态效果设置:
SettingsController
*
settings
=
[[SettingsController alloc]initWithNibName:
@"
SettingsView
"
bundle:nil];
settings.modalTransitionStyle
=
UIModalTransitionStyleFlipHorizontal;
//
水平翻转
[self presentModalViewController:settings animated:YES];
[settings release];
9.NSScrollView 滑动用法:
-
(
void
) scrollViewDidScroll:(UIScrollView
*
)scrollView{
NSLog(
@"
正在滑动中...
"
);
}
//
用户直接滑动NSScrollView,可以看到滑动条
-
(
void
) scrollViewDidEndDecelerating:(UIScrollView
*
)scrollView {
}
//
通过其他控件触发NSScrollView滑动,看不到滑动条
-
(
void
) scrollViewDidEndScrollingAnimation:(UIScrollView
*
)scrollView {
}
10. 读取全局的Delegate:
KiloNetAppDelegate
*
appdelegate
=
(KiloNetAppDelegate
*
)[[UIApplication sharedApplication]
delegate
];
11.键盘处理系列
//set the UIKeyboard to switch to a different text field when you press return
//
switch textField to the name of your textfield
[textField becomeFirstResponder];
12. 半透明层的实现:
半透明层
+
(
void
)showWaiting:(UIView
*
)parent {
int
width
=
32
, height
=
32
;
CGRect frame
=
[parent frame];
//
[[UIScreen mainScreen] applicationFrame];
int
x
=
frame.size.width;
int
y
=
frame.size.height;
frame
=
CGRectMake((x
-
width)
/
2
, (y
-
height)
/
2
, width, height);
UIActivityIndicatorView
*
progressInd
=
[[UIActivityIndicatorView alloc] initWithFrame:frame];
[progressInd startAnimating];
progressInd.activityIndicatorViewStyle
=
UIActivityIndicatorViewStyleWhiteLarge;
//
frame = CGRectMake((x - 140)/2, (y - height) / 2 + height, 140, 30);
//
UILabel *waitingLable = [[UILabel alloc] initWithFrame:frame];
//
waitingLable.text = @"Proccesing...";
//
waitingLable.textColor = [UIColor whiteColor];
//
waitingLable.font = [UIFont systemFontOfSize:15];
//
waitingLable.backgroundColor = [UIColor clearColor];
frame
=
[parent frame];
UIView
*
theView
=
[[UIView alloc] initWithFrame:frame];
theView.backgroundColor
=
[UIColor blackColor];
theView.alpha
=
0.8
;
[theView addSubview:progressInd];
//
[theView addSubview:waitingLable];
[progressInd release];
//
[waitingLable release];
[theView setTag:
9999
];
[parent addSubview:theView];
[theView release];
}
+
(
void
)hideWaiting:(UIView
*
)parent {
[[parent viewWithTag:
9999
] removeFromSuperview];
}
13. 设置View的圆角:
// 首先应用 #import <QuartzCore/QuartzCore.h>
view.layer.cornerRadius
=
10
;
view.layer.masksToBounds
=
YES;
14. UIWebView显示本地图片(目前有点问题,无法正确显示图片):
代码
NSString
*
imagePath
=
[[NSBundle mainBundle] resourcePath];
imagePath
=
[imagePath stringByReplacingOccurrencesOfString:
@"
/
"
withString:
@"
//
"
];
imagePath
=
[imagePath stringByReplacingOccurrencesOfString:
@"
"
withString:
@"
%20
"
];
NSLog(
@"
fileurl=%@
"
,[NSString stringWithFormat:
@"
file:/%@//
"
,imagePath]);
//
[self loadData:[html dataUsingEncoding:NSUTF8StringEncoding] MIMEType:@"text/html" textEncodingName:@"UTF-8" baseURL:[NSURL fileURLWithPath:[NSString stringWithFormat:@"file:/%@
//
",imagePath]] ];
[self loadHTMLString:html baseURL:[NSURL fileURLWithPath:[NSString stringWithFormat:
@"
file:/%@//
"
,imagePath] ]];
NSString *path = [[NSBundle mainBundle] bundlePath];
NSURL
*
baseURL
=
[NSURL fileURLWithPath:path];
[UIWebView loadHTMLString:html baseURL:baseURL];
//
这段代码可以正确显示图片。