NSUserDefaults的用法
NSDictionary* defaults = [[NSUserDefaults standardUserDefaults] dictionaryRepresentation]; NSLog(@"Defaults: %@", defaults);
是用来获取设备上的所有的NSUserDefaults的设置。
上面代码输出了
2013-06-26 12:41:09.948 MyText[5180:c07] Defaults: {
AppleITunesStoreItemKinds = (
wemix,
podcast,
document,
"software-update",
newsstand,
"tv-episode",
"tv-season",
software,
audiobook,
movie,
song,
album,
tone,
booklet,
ringtone,
artist,
"podcast-episode",
"itunes-u",
mix,
eBook
);
AppleLanguages = (
en,
"zh-Hans",
"zh-Hant",
fr,
de,
ja,
nl,
it,
es,
pt,
"pt-PT",
da,
fi,
nb,
sv,
ko,
ru,
pl,
tr,
uk,
ar,
hr,
cs,
el,
he,
ro,
sk,
th,
id,
ms,
"en-GB",
ca,
hu,
vi
);
AppleLocale = "en_US";
NSInterfaceStyle = macintosh;
NSLanguages = (
en,
"zh-Hans",
"zh-Hant",
fr,
de,
ja,
nl,
it,
es,
pt,
"pt-PT",
da,
fi,
nb,
sv,
ko,
ru,
pl,
tr,
uk,
ar,
hr,
cs,
el,
he,
ro,
sk,
th,
id,
ms,
"en-GB",
ca,
hu,
vi
);
}
如果想单独看某个key的设置，例如:
NSArray *array = [[NSUserDefaults standardUserDefaults] objectForKey:@"AppleKeyboards"]; NSLog(@"Keyboards: %@", array);
会输出
AppleKeyboards = ( "zh_Hans-Pinyin@sw=Pinyin;hw=US", "en_US@hw=US;sw=QWERTY" );
用法：
//保存数据到NSUserDefaults
-(void)saveNSUserDefaults
{
NSString *myString = @"enuola";
int myInteger = 100;
float myFloat = 50.0f;
double myDouble = 20.0;
NSDate *myDate = [NSDate date];
NSArray *myArray = [NSArray arrayWithObjects:@"hello", @"world", nil];
NSDictionary *myDictionary = [NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:@"enuo", @"20", nil] forKeys:[NSArray arrayWithObjects:@"name", @"age", nil]];
//将上述数据全部存储到NSUserDefaults中
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
//存储时，除NSNumber类型使用对应的类型意外，其他的都是使用setObject:forKey:
[userDefaults setInteger:myInteger forKey:@"myInteger"];
[userDefaults setFloat:myFloat forKey:@"myFloat"];
[userDefaults setDouble:myDouble forKey:@"myDouble"];
[userDefaults setObject:myString forKey:@"myString"];
[userDefaults setObject:myDate forKey:@"myDate"];
[userDefaults setObject:myArray forKey:@"myArray"];
[userDefaults setObject:myDictionary forKey:@"myDictionary"];
//这里建议同步存储到磁盘中，但是不是必须的
[userDefaults synchronize];
}
//从NSUserDefaults中读取数据
-(void)readNSUserDefaults
{
NSUserDefaults *userDefaultes = [NSUserDefaults standardUserDefaults];
//读取数据到各个label中
//读取整型int类型的数据
NSInteger myInteger = [userDefaultes integerForKey:@"myInteger"];
txtInteger.text = [NSString stringWithFormat:@"%d",myInteger];
//读取浮点型float类型的数据
float myFloat = [userDefaultes floatForKey:@"myFloat"];
txtFloat.text = [NSString stringWithFormat:@"%f",myFloat];
//读取double类型的数据
double myDouble = [userDefaultes doubleForKey:@"myDouble"];
txtDouble.text = [NSString stringWithFormat:@"%f",myDouble];
//读取NSString类型的数据
NSString *myString = [userDefaultes stringForKey:@"myString"];
txtNSString.text = myString;
//读取NSDate日期类型的数据
NSDate *myDate = [userDefaultes valueForKey:@"myDate"];
NSDateFormatter *df = [[NSDateFormatter alloc] init];
[df setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
txtNSDate.text = [NSString stringWithFormat:@"%@",[df stringFromDate:myDate]];
//读取数组NSArray类型的数据
NSArray *myArray = [userDefaultes arrayForKey:@"myArray"];
NSString *myArrayString = [[NSString alloc] init];
for(NSString *str in myArray)
{
NSLog(@"str= %@",str);
myArrayString = [NSString stringWithFormat:@"%@ %@", myArrayString, str];
[myArrayString stringByAppendingString:str];
// [myArrayString stringByAppendingFormat:@"%@",str];
NSLog(@"myArrayString=%@",myArrayString);
}
txtNSArray.text = myArrayString;
//读取字典类型NSDictionary类型的数据
NSDictionary *myDictionary = [userDefaultes dictionaryForKey:@"myDictionary"];
NSString *myDicString = [NSString stringWithFormat:@"name:%@, age:%d",[myDictionary valueForKey:@"name"], [[myDictionary valueForKey:@"age"] integerValue]];
txtNSDictionary.text = myDicString;
}
用NSUserDefaults存储的数据下次程序运行的时候依然存在，它把数据存储在什么地方了？如何能够清除？
其实它存储在应用程序内置的一个plist文件里，这个可以根据路径看到。
比如说这个是你的程序沙盒位置
/UsersLibrary/Application Support/iPhoneSimulator/4.1/Applicati*****/29788E40-AF47-45A0-8E92-3AC0F501B7F4/,（这个是应用程序对应在mac上的位置）
这个下面有/Library/Prefereces，里面有个plist文件，存储的就是你的userDefaults
想要删掉的话，用removeObjectForKey或者删掉沙盒，也就是你的应用程序然后重新安装。
这个plist文件在NsUserDefaults使用之前是没有的。
CCUserDefault和NSUserDefaults差不多，地址是：
std::string dir = CCUserDefault::sharedUserDefault()->getXMLFilePath();
CCLOG("dir:%s",dir.c_str());
dir:/Users/liulijun/Library/Application Support/iPhone Simulator/6.1/Applications/5135A000-024F-468E-99F0-F75FABC1392A/Library/Caches/UserDefault.xml
方法：
/** @brief Set bool value by key. */ void setBoolForKey(const char* pKey, bool value); /** @brief Set integer value by key. */ void setIntegerForKey(const char* pKey, int value); /** @brief Set float value by key. */ void setFloatForKey(const char* pKey, float value); /** @brief Set double value by key. */ void setDoubleForKey(const char* pKey, double value); /** @brief Set string value by key. */ void setStringForKey(const char* pKey, const std::string & value); /** @brief Save content to xml file */ void flush();
ps：
NSUserDefaults读取和写入自定义对象
http://blog.csdn.net/chyroger/article/details/5785297