C++ Vector

vector< int > ivec( 10, -1 );
定义了 ivec 它包含十个 int 型的元素 每个元素都被初始化为-1

// 把ia的6个元素拷贝到ivec中
vector< int > ivec( ia, ia+6 );
可以将 vector 初始化为一个已有数组的全部或一部分 只需指定希望被用来初始化 vector 的数组的开始地址以及数组最末元素的下一位置来实现

//拷贝3个元素 ia[2],ia[3],ia[4]
vector< int > ivec( &ia[ 2 ], &ia[ 5 ] );

与内置数组不同 vector 可以被另一个 vector 初始化 或被赋给另一个 vector
例如 vector< string > svec;

vector< string > svec;

void init_and_assign()
{
        // 用另一个 vector 初始化一个 
        vector vector< string > user_names( svec );
         // ...
        // 把一个 vector 拷贝给另一个 
        vector svec = user_names;
}

C++ 标准 STL(Standard Template Library)

在C++标准中，STL被组织为下面的13个头文件：

algorithm, deque, functional, iterator, 
vector, list, map, memory, numeric, 
queue, set, stack和utility

C++ 引用和指针的区别

指针和引用有两个主要区别 引用必须总是指向一个对象 如果用一个引用给另一个引 用赋值 那么改变的是被引用的对象而不是引用本身 让我们来看几个例子 当我们这样写
int *pi = 0;
用 0 初始化 pi——即 pi 当前不指向任何对象 但当我们写如下语句时 const int &ri = 0;
在内部 发生了以下转换
int temp = 0; const int &ri = temp;
引用之间的赋值是第二个不同 当给定了以下代码后
int ival = 1024, ival2 = 2048; int *pi = &ival, *pi2 = &ival2;
我们再写如下语句
pi = pi2;
pi 指向的对象 ival 并没有被改变 实际上 pi 被赋值为指向 pi2 所指的对象——在本例中 即 ival2 重要的是 现在 pi 和 pi2 都指向同一对象 这是一个重要的错误源 如果我们把 一个类对象拷贝给另一个类对象 而该类有一个或多个成员是指针 我们将在第 14 章详细讨 论这个问题
但是 假定有下列代码
int &ri = ival, &ri2 = ival2;
当我们写出这样的赋值语句时
ri = ri2;
改变的是 ival
而不是引用本身 赋值之后 两个引用仍然指向原来的对象 实际的 C++程序很少使用指向独立对象的引用类型 引用类型主要被用作函数的形式参数

Drawing with NSBezierPath

@interface StretchView : NSView {
 NSBezierPath *path;
}
- (NSPoint)randomPoint;

@end

@implementation StretchView

- (id)initWithFrame:(NSRect)frame {
    if (![super initWithFrame:frame]) 
  return nil;
 
 srandom(time(NULL));
 
 path = [[NSBezierPath alloc] init];
 [path setLineWidth:3.0];
 NSPoint p = [self randomPoint];
 [path moveToPoint:p];
 int i;
    for (i = 0; i < 15; i++) {
  p = [self randomPoint];
  [path lineToPoint:p];
 }
 [path closePath];
 return self;
}

- (void)dealloc
{
 [path release];
 [super dealloc];
}

- (NSPoint)randomPoint
{
 NSRect bounds = [self bounds];
 NSPoint result;
 result.x = bounds.origin.x + random() % (int)bounds.size.width;
 result.y = bounds.origin.y + random() % (int)bounds.size.height;
 return result;
}

- (void)drawRect:(NSRect)rect {
 NSRect bounds = [self bounds];
 [[NSColor greenColor] set];
 [NSBezierPath fillRect:bounds];
 
 [[NSColor whiteColor] set];
 [path fill];
 
}

@end

logging in iPhone Applications

NSData *dataToWrite = [[NSString stringWithString:@"String to write"] dataUsingEncoding:NSUTF8StringEncoding];

NSString *docsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *path = [docsDirectory stringByAppendingPathComponent:@"fileName.txt"];

// Write the file
[dataToWrite writeToFile:path atomically:YES];

// Read the file
NSString *stringFromFile = [[NSString alloc] initWithContentsOfFile:path]; 

// Check if file exists
NSFileManager *fileManager = [NSFileManager defaultManager];
[fileManager fileExistsAtPath:path]; // Returns a BOOL   

// Remove the file
[fileManager removeItemAtPath:path error:NULL];

// Cleanup
[stringFromFile release];
[fileManager release];

White log into the log-file

+ (void)logGenenalInfo:(NSString *)data {
 NSString *docsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
 NSString *path = [docsDirectory stringByAppendingPathComponent:@"GeneralFile.txt"];
 
 // Check if file exists
 NSFileManager *fileManager = [NSFileManager defaultManager];
 if ([fileManager fileExistsAtPath:path]) {
  // Read the file
  NSString *stringFromFile = [[NSString alloc] initWithContentsOfFile:path];
  data = [stringFromFile stringByAppendingFormat:@" %@",data];
 }
 NSData *dataToWrite = [data dataUsingEncoding:NSUTF8StringEncoding];
 // Write the file
 [dataToWrite writeToFile:path atomically:YES];
 [fileManager release];
}

Clean the Log

+ (void)cleanAllLog {
 NSFileManager *fileManager = [NSFileManager defaultManager];
 
 NSString *docsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
 NSString *gePath = [docsDirectory stringByAppendingPathComponent:@"GeneralFile.txt"];
 
 
 // Check if file exists then Remove the file
 if ([fileManager fileExistsAtPath:gePath]) // Returns a BOOL    
  [fileManager removeItemAtPath:gePath error:NULL];
 
 [fileManager release];
}

Get the program information

DateTime\tMessage\tData\tfileNameAndLineNumber

[LogFileHelper logGenenalInfo:
[NSString stringWithFormat:@"function %s, line %d \n"
,__FUNCTION__,__LINE__]];

iPhone-format

-(NSString*) formatCurrencyValue:(double)value
{
  NSNumberFormatter *numberFormatter = [[NSNumberFormatter alloc] init];
  [numberFormatter setFormatterBehavior:NSNumberFormatterBehavior10_4];
  [numberFormatter setCurrencySymbol:@"$"];
  [numberFormatter setNumberStyle:NSNumberFormatterCurrencyStyle];
  NSNumber *c = [NSNumber numberWithFloat:value];
  return [numberFormatter stringFromNumber:c];
}

-(NSString*) formatPercentValue:(double)value
{
  NSNumberFormatter *numberFormatter = [[NSNumberFormatter alloc] init];
  [numberFormatter setFormatterBehavior:NSNumberFormatterBehavior10_4];
  [numberFormatter setPercentSymbol:@"%"];
  [numberFormatter setNumberStyle: NSNumberFormatterPercentStyle];
  [numberFormatter setDecimalSeparator:@"."];
  [numberFormatter setGeneratesDecimalNumbers:TRUE];
  [numberFormatter setMinimumFractionDigits:2];
  [numberFormatter setRoundingMode: NSNumberFormatterRoundUp];
  [numberFormatter setRoundingIncrement:[[NSNumber alloc]initWithDouble:0.05]];
  NSNumber *c = [NSNumber numberWithFloat:value];
  return [numberFormatter stringFromNumber:c];
}

-(double) formatDoubleFromCurrency:(NSString*)value
{
  double ret ;
  if(value)
  {
    ret = [value doubleValue];
    if (ret == 0)
     {
      NSNumberFormatter *numberFormatter = [[NSNumberFormatter alloc] init];
      [numberFormatter setFormatterBehavior:NSNumberFormatterBehavior10_4];
      [numberFormatter setCurrencySymbol:@"$"];
      [numberFormatter setNumberStyle:NSNumberFormatterCurrencyStyle];
      NSNumber *c = [numberFormatter numberFromString:value];
      ret = [c doubleValue];
     }
     return ret;
  }
  else
    return 0.0;
}

Password Encryption

#import 

@interface Encryption : NSObject {
}

+ (NSString *) md5: (NSString *) plainText;

@end

#import "Encryption.h"
#import 

@implementation Encryption

+ (NSString *) md5: (NSString *) plainText {
 const char *cStr = [plainText UTF8String];
 unsigned char result[CC_MD5_DIGEST_LENGTH];
 CC_MD5(cStr, strlen(cStr), result);
 
 return [[NSString stringWithFormat: @"%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",
    result[0], result[1], result[2], result[3],
    result[4], result[5], result[6], result[7],
    result[8], result[9], result[10], result[11],
    result[12], result[13], result[14], result[15]
    ] lowercaseString];
}

@end

+(NSString*)fileMD5:(NSString*)path
{
    NSFileHandle *handle = [NSFileHandle fileHandleForReadingAtPath:path];
    if( handle== nil ) return @"ERROR GETTING FILE MD5"; // file didnt exist
 
    CC_MD5_CTX md5;
 
    CC_MD5_Init(&md5);
 
    BOOL done = NO;
    while(!done)
    {
        NSData* fileData = [handle readDataOfLength: CHUNK_SIZE ];
        CC_MD5_Update(&md5, [fileData bytes], [fileData length]);
        if( [fileData length] == 0 ) done = YES;
    }
    unsigned char digest[CC_MD5_DIGEST_LENGTH];
    CC_MD5_Final(digest, &md5);
    NSString* s = [NSString stringWithFormat: @"%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
                   digest[0], digest[1], 
                   digest[2], digest[3],
                   digest[4], digest[5],
                   digest[6], digest[7],
                   digest[8], digest[9],
                   digest[10], digest[11],
                   digest[12], digest[13],
                   digest[14], digest[15]];
    return s;
}

IPHONE APP 真正的全局变量

真正牛B 的全局变量是 定义在 main（）里面的。。。。
可以直接用。。。。

iPhone-country code and iPhone locale settings

March 19, 2009 — praveenmatanam

NSLocale *locale = [NSLocale currentLocale];
NSString *countryCode = [locale objectForKey: NSLocaleCountryCode];

NSString *countryName = [locale displayNameForKey: NSLocaleCountryCode
value: countryCode]];

Process status

ps -ax -o user,pid,vsz,rss,command

USER       PID      VSZ    RSS COMMAND
root         1  2456680   1048 /sbin/launchd
root        10  2448264   2564 /usr/libexec/kextd
root        11  2444540    736 /usr/sbin/notifyd
root        12  2446808   1440 /usr/sbin/diskarbitrationd
root        13  2462636   3164 /usr/libexec/configd
root        14  2457096    852 /usr/sbin/syslogd
root        15  2452816   5012 /usr/sbin/DirectoryService
daemon      16  2446660   1596 /usr/sbin/distnoted
root        18  2459016   2452 /usr/sbin/cupsd -l
_usbmuxd    20  2460984   2024 /System/Library/PrivateFrameworks/MobileDevice.f
root        21  2446688   1008 /sbin/SystemStarter
root        24  2459344   3560 /usr/sbin/securityd -i
root        27  2809672 137060 /System/Library/Frameworks/CoreServices.framewor
_mdnsresponder    28  2459704   2376 /usr/sbin/mDNSResponder -launchd
ming        29  2777832  11236 /System/Library/CoreServices/loginwindow.app/Con
root        30  2445744    992 /usr/sbin/KernelEventAgent
root        32  2447564   2064 /usr/libexec/hidd
root        33  2464044   2560 /System/Library/Frameworks/CoreServices.framewor
root        35  2434784    788 /sbin/dynamic_pager -F /private/var/vm/swapfile
root        40  2461604   4260 /usr/sbin/blued
root        41  2445648    936 autofsd
root        45   105636   2792 /Library/Application Support/iStat Server/iStatS
root        49  2492500  27688 /System/Library/CoreServices/coreservicesd
_windowserver    60  2900984 110808 /System/Library/Frameworks/ApplicationServices.f
root        74    81940    444 /Library/Application Support/VMware Fusion/vmnet
root        80    81536    296 /Library/Application Support/VMware Fusion/vmnet
root        82    77668    176 /Library/Application Support/VMware Fusion/vmnet
root        85    77668    176 /Library/Application Support/VMware Fusion/vmnet
root        88    81536    288 /Library/Application Support/VMware Fusion/vmnet
root        90    88520    500 /Library/Application Support/VMware Fusion/vmnet
root        93  2438116    848 /System/Library/Frameworks/OpenGL.framework/Vers
_coreaudiod   104  2453356   6160 /usr/sbin/coreaudiod
ming       109  2456228   1100 /sbin/launchd
ming       113  2946424  22388 /System/Library/CoreServices/Dock.app/Contents/M
ming       114  2782252  20648 /System/Library/CoreServices/SystemUIServer.app/
ming       115  3109228  59456 /System/Library/CoreServices/Finder.app/Contents
ming       119  2435928    836 /usr/sbin/pboard
ming       122  2507916   5176 /System/Library/Frameworks/ApplicationServices.f
ming       127  2462084   1964 /System/Library/Frameworks/InputMethodKit.framew
ming       130  2725340   5648 /usr/libexec/UserEventAgent -l Aqua
ming       136  2447976   1644 /System/Library/CoreServices/AirPort Base Statio
ming       143  2727672   4876 /Applications/iTunes.app/Contents/Resources/iTun
ming       146   382580   2352 /Library/PreferencePanes/Microsoft Mouse.prefPan
ming       148   433900   7896 /Library/PreferencePanes/MaxMenus.prefPane/Conte
ming       149   387344   3768 /Users/ming/Library/Application Support/RealNetw
ming       150   502728  63288 /Applications/Dropbox.app/Contents/MacOS/Dropbox
root       153    98728  13328 /Users/ming/Library/Application Support/RealNetw
ming       157  2755412   7724 /System/Library/Image Capture/Support/Image Capt
ming       169   493260  15104 /Library/PreferencePanes/Growl.prefPane/Contents
root       186   602372   1432 /Applications/Dropbox.app/Contents/Resources/dbf
ming       191  2468332   9020 /System/Library/Services/AppleSpell.service/Cont
ming       208  2891412 299268 /System/Library/Frameworks/CoreServices.framewor
ming       319  2860440  38044 /System/Library/Input Methods/SCIM.app/Contents/
ming       367  2181412 341968 /Applications/Firefox.app/Contents/MacOS/firefox
ming       395   602576  94244 /Applications/Microsoft Office 2008/Microsoft Po
ming       398   424872   7724 /Applications/Microsoft Office 2008/Office/Micro
ming       400   368980   2116 /Library/Application Support/Microsoft/MAU2.0/Mi
ming       523   634040  47896 /Applications/iTunes.app/Contents/MacOS/iTunes -
ming       524   110844   9796 /System/Library/PrivateFrameworks/MobileDevice.f
ming       725 11324624  83240 /Developer/Applications/Xcode.app/Contents/MacOS
ming       954  2864280  15080 /Applications/Utilities/Terminal.app/Contents/Ma
ming      1360  2855608  49036 /Applications/Mail.app/Contents/MacOS/Mail -psn_
ming      1458  2458404   1412 /usr/bin/ssh-agent -l
ming      1692   501360  14980 /Applications/TextWrangler.app/Contents/MacOS/Te
ming      1695   101004    956 /Applications/TextWrangler.app/Contents/Helpers/
ming      2381  2775268  24184 /Applications/iCal.app/Contents/MacOS/iCal -psn_
ming      2403  3033012  94076 /Applications/Preview.app/Contents/MacOS/Preview
_lp       4284  2467040  32676 Brother_HL_2170W_series 7 ming 1-02 Session 101 
root      4285  2435912    840 mdns://Brother%20HL-2170W%20series._pdl-datastre
ming      4294   691276  73032 /Applications/QQ.app/Contents/MacOS/QQ -psn_0_99
root      4538  2436056   1588 login -pf ming
ming      4539  2435468   1092 -bash
root      5099  2434788    516 ps -ax -o user,pid,vsz,rss,command

Play sound

#import 


@interface CSSound : NSObject {
 
}
+(void)playSound:(NSString *)soundName;
@end

#import "CSSound.h"
#import 

@implementation CSSound
+(void)playSound:(NSString *)soundName{
 SystemSoundID mySSID;
 NSString *path = [[[NSBundle mainBundle] resourcePath] stringByAppendingString:soundName];
 
 OSStatus error = AudioServicesCreateSystemSoundID( (CFURLRef)[NSURL fileURLWithPath:path], &mySSID);
 
 if(error == kAudioServicesNoError){
  //DLog(@"successfully contructed sound %@", soundName);
  AudioServicesPlaySystemSound(mySSID);
 }else{
  DLog(@"error playing sound %@", soundName);
 }
}

gcc Unix&Mac OS program (3. Predefined macros)

__APPLE__ : Defined for an Apple Platform, such as OS X.
__APPLE_CC__ : This is an integer value representing the version of the compiler.
__OBJC__ : Defined if the compiler is compiling in Objective-C mode
__cplusplus : Defined if the compiler is compiling in C++ mode.
__MACH__ : Defined if the Mach system calls are available
__DATE__ : The current date
__TIME__ : The current time
__FILE__ : The name of file
__LINE__ : The line number of the file
__FUNCTION__ : The name of the function r Objective-C method being compiled

// predef.m -- play with predefined macros

/* compile with
cc -g -Wall -o predef -framework Foundation predef.m
*/


#import 
#import 

void someFunc (void)
{
    printf ("file %s, line %d, function %s\n", __FILE__, __LINE__, __FUNCTION__);
} // someFunc

@interface SomeClass : NSObject { } 
+ (void) someMethod;
@end

@implementation SomeClass
+ (void) someMethod
{
    printf ("file %s, line %d, function %s\n", __FILE__, __LINE__, __FUNCTION__);
} // someMethod
@end

int main (int argc, char *argv[])
{
    printf ("__APPLE__: %d,  __APPLE_CC__: %d\n",
     __APPLE__, __APPLE_CC__);
    printf ("today is %s, the time is %s\n", __DATE__, __TIME__);
    printf ("file %s, line %d, function %s\n", __FILE__, __LINE__, __FUNCTION__);
    someFunc ();
    [SomeClass someMethod];
    return (0);
} // main

cc -g -Wall -o predef -framework Foundation predef.m

./predef

__APPLE__: 1, __APPLE_CC__: 5657
today is Feb 1 2010, the time is 12:32:23
file predef.m, line 32, function main
file predef.m, line 13, function someFunc
file predef.m, line 23, function +[SomeClass someMethod]

gcc Unix&Mac OS program (2. assemble resulting file)

cc -g -Wall -S XXXX.m

cc -o xxxx xxxx.s

gcc Unix&Mac OS program (1. Warning)

int main (int arg, char *argv)
{
 int i;
}

terminal command: cc -Wall -o warning warning.m

warning.m:2: warning: second argument of ‘main’ should be ‘char **’
warning.m: In function ‘main’:
warning.m:3: warning: unused variable ‘i’
warning.m:4: warning: control reaches end of non-void function

/*
* cc - Wall -Wno-unused warning.m (turn that unused warning off)
*/

/*
* cc -Wunused warning.m (only see unused warning mistakes)
*/