【bolg目標】

bolg僅僅針對<Cocoa原理指南>書中代碼進行本地測試和文檔學習，書中理論不進行摘要

個人覺得此書值得推薦閱讀，從整體上學習Cocoa

【實踐環境】
Mac 10.6
XCode4

【正文】
Pdf版

Cocoa整體縱覽圖，在書中頁碼：
Foundation
　　P15
　　P16
　　P17
Application Kit
　　P20
　　P21

/**************************************************/
下面分析下P27書中代碼

#import <Foundation/Foundation.h>
int main (int argc, const char * argv[]) {
??? NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
??? NSArray *args = [[NSProcessInfo processInfo] arguments];
??? NSCountedSet *cset = [[NSCountedSet alloc] initWithArray:args];
??? NSArray *sorted_args = [[cset allObjects]
??????????????????????????? sortedArrayUsingSelector:@selector(compare:)];
??? NSEnumerator *enm = [sorted_args objectEnumerator];
??? id word;
??? while (word = [enm nextObject]) {
??????? printf("%s\n", [word UTF8String]);
??? }
???
??? [cset release];
??? [pool release];
??? return 0;
}

比對資料學習，如下
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

NSProcessInfo

此類是對當前進程信息的訪問

The NSProcessInfo class provides methods to access information about the current process. Each process has a single, shared NSProcessInfo object, known as process information

agent.

Getting the Process Information Agent
+ processInfo
Accessing Process Information
– arguments
– environment
– processIdentifier
– globallyUniqueString
– processName
– setProcessName:
Sudden Application Termination
– disableSuddenTermination
– enableSuddenTermination
Getting Host Information
– hostName
– operatingSystem
– operatingSystemName
– operatingSystemVersionString
Getting Computer Information
– physicalMemory
– processorCount
– activeProcessorCount
– systemUptime

關于上面羅列的，一目了然的明白這些方法的目的

本例使用processInfo和arguments

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

NSCountedSet 繼承NSMutableSet : NSSet : NSObject

The NSCountedSet class declares the programmatic interface to a mutable, unordered collection of indistinct objects. A counted set is also known as a bag.

在本例，此類用于統計重復輸入對象，在后續的調整代碼有這么一句輸出
NSLog(@"%@,%lu" ,item ,[cset countForObject:item]);

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

sortedArrayUsingSelector:屬于NSArray類的，用于數組排序
@selector(compare:)，通過文檔，發現其中compare:這個函數來自NSNumber類{?這個是現行理解}，其原型：
- (NSComparisonResult)compare:(NSNumber *)aNumber

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

按照書中描述，
SimpleCocoaTool a z c a l q m z
a
c
l
m
q
z

實際在調試中發現出現數據類似
/Users/...../SimpleCocoaTool
a
c
l
m
q
z

比書中所寫代碼多一個行輸出

至于為什么會這樣，要么書中作者截獲，要么Xcode版本問題
下面在XCode4下進行下面改進
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

為了在調試中實踐，最后結果類似書中類似輸出，改進原有代碼：
int main (int argc, const char * argv[]) {
??? NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
???
??? NSMutableArray *args = [[NSMutableArray alloc] initWithArray:[[NSProcessInfo processInfo] arguments]];//把NSArray換成NSMutableArray
???
??? [args removeObjectAtIndex:0];//移出第一個參數
???
??? NSCountedSet *cset = [[NSCountedSet alloc] initWithArray:args];
???
??? for(id item in cset)
??? {
??????? NSLog(@"%@,%lu" ,item ,[cset countForObject:item]);
??? }
???
??? NSArray *sorted_args = [[cset allObjects]
??????????????????????????? sortedArrayUsingSelector:@selector(compare:)];
??? NSEnumerator *enm = [sorted_args objectEnumerator];
??? id word;
??? while (word = [enm nextObject]) {
??????? printf("%s\n", [word UTF8String]);
??? }
???
??? for(id item in sorted_args)
??? {
??????? NSLog(@"for %@" ,item);
??? }
???
??? [cset release];
??? [pool release];
???
??? return 0;
}

現在測試

SimpleCocoaTool a z c a l q m z
a
c
l
m
q
z
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

轉載于:https://www.cnblogs.com/GoGoagg/archive/2011/08/24/2152032.html

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