实现在ios文件读写

文件都是用来读写数据的，可是哪里都会有潜规则，ios里面读写数据的潜规则你知不知道，你知道不知道！！！

你有没有觉得NSUserDefaults和NSBundle，plist这些玩意阴魂不散，有时候搞不清楚谁是谁。谁又会在哪里出现

看看下面，NSUserDefaults里面基本没存啥啊，只有语言国度对不对，剩下的是自己填的，是嘛

[NSUserDefaults standardUserDefaults]可以用来保存：NSString, NSNumber, NSDate, NSArray, NSDictionary。
系统默认保存到/Library/Preferences/.plist这个文件中

写入数据：
//Bool
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
[userDefaults setBool:YES forKey:@"switchValue"];
 
//String
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
[userDefaults setObject:@"star" forKey:@"inputValue"];

读取数据：
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
BOOL sw = [userDefaults boolForKey:@"switchValue"];
 
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
NSString *str = [userDefaults stringForKey:@"inputValue"];

默认的
 [[NSUserDefaults standardUserDefaults] dictionaryRepresentation]:{
    AppleITunesStoreItemKinds =     (
        eBook,
        document,
        "software-update",
        booklet,
        "itunes-u",
        newsstand,
        artist,
        podcast,
        "podcast-episode",
        software
    );
    AppleLanguages =     (
        "zh-Hans",
        en,
        fr,
        de,
        ja,
        nl,
        it,
        es,
        pt,
        "pt-PT",
        da,
        fi,
        nb,
        sv,
        ko,
        "zh-Hant",
        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 =     (
        "zh-Hans",
        en,
        fr,
        de,
        ja,
        nl,
        it,
        es,
        pt,
        "pt-PT",
        da,
        fi,
        nb,
        sv,
        ko,
        "zh-Hant",
        ru,
        pl,
        tr,
        uk,
        ar,
        hr,
        cs,
        el,
        he,
        ro,
        sk,
        th,
        id,
        ms,
        "en-GB",
        ca,
        hu,
        vi
    );
}

NSBundle这斯里面存了比NSUserDefaults里面多得多的东西啊，怎么分配的哦

程序版本号，程序名称，路径，启动nib，好嘛。。。。

NSBundle mainBundle:{
    CFBundleDevelopmentRegion = English;
    CFBundleDisplayName = iVersion;
    CFBundleExecutable = iVersion;
    CFBundleExecutablePath = "/Users/yongjack/Library/Application Support/iPhone Simulator/6.1/Applications/D0556446-FFD6-4C33-81F2-5917B48907F6/iVersion.app/iVersion";
    CFBundleIdentifier = "com.charcoaldesign.iVersion";
    CFBundleInfoDictionaryVersion = "6.0";
    CFBundleInfoPlistURL = "Info.plist -- file://localhost/Users/yongjack/Library/Application%20Support/iPhone%20Simulator/6.1/Applications/D0556446-FFD6-4C33-81F2-5917B48907F6/iVersion.app/";
    CFBundleName = iVersion;
    CFBundlePackageType = APPL;
    CFBundleSignature = "????";
    CFBundleSupportedPlatforms =     (
        iPhoneSimulator
    );
    CFBundleVersion = "1.0";
    DTPlatformName = iphonesimulator;
    DTSDKName = "iphonesimulator6.1";
    LSRequiresIPhoneOS = 1;
    NSBundleInitialPath = "/Users/yongjack/Library/Application Support/iPhone Simulator/6.1/Applications/D0556446-FFD6-4C33-81F2-5917B48907F6/iVersion.app";
    NSBundleResolvedPath = "/Users/yongjack/Library/Application Support/iPhone Simulator/6.1/Applications/D0556446-FFD6-4C33-81F2-5917B48907F6/iVersion.app";
    NSMainNibFile = MainWindow;
    UIDeviceFamily =     (
        1
    );
    UISupportedInterfaceOrientations =     (
        UIInterfaceOrientationPortrait,
        UIInterfaceOrientationPortraitUpsideDown,
        UIInterfaceOrientationLandscapeLeft,
        UIInterfaceOrientationLandscapeRight
    );
}

NSDocumentDirectory    <Application_Home>/Documents        
 


NSCachesDirectory    <Application_Home>/Library/Caches        
 


NSApplicationSupportDirectory    <Application_Home>/Library/Application Support