IOS 常用字串的操作

weixin_33807284發表於2016-11-23

IOS 常用字串的操作

不可變字串

將NSData轉化為NSString
 NSString* str = [[NSString alloc] initWithData:response encoding:NSUTF8StringEncoding];
將NSString 轉化為NSData
  - (NSData *)dataUsingEncoding:(NSStringEncoding)encoding;  
載一個字串中刪除一個字元或字串
 [_display deleteCharactersInRange:NSMakeRange(index_of_char_to_remove, 1)];
數學轉換為字串
 NSString *returnStr;
 returnStr = [[NSNumber numberWithInt:row] stringValue];

建立字串的方法

1、建立常量字串。
 NSString *astring = @"This is a String!";  
2、建立空字串,給予賦值.
 NSString *astring = [[NSString alloc] init];  
 astring = @"This is a String!";  
 [astring release];  
 NSLog(@"astring:%@",astring);  
3、在以上方法中,提升速度:initWithString方法
  NSString *astring = [[NSString alloc] initWithString:@"This is a String!"];  
  NSLog(@"astring:%@",astring); 
  [astring release];  
4、用標準c建立字串:initWithCString方法
  char *Cstring = "This is a String!";
  NSString *astring = [[NSString alloc] initWithCString:Cstring];  
  NSLog(@"astring:%@",astring);  
  [astring release];  
5、建立格式化字串:佔位符(由一個%加一個字元組成)
 int i = 1;  
 int j = 2;  
 NSString *astring = [[NSString alloc] initWithString:[NSString stringWithFormat:@"%d.This is %i string!",i,j]];  
 NSLog(@"astring:%@",astring);  
 [astring release];  
6、建立臨時字串
  NSString *astring; 
  astring = [NSString stringWithCString:"This is a temporary string"];  
  NSLog(@"astring:%@",astring);  

從檔案讀取字串:initWithContentsOfFile方法

 NSString *path = @"astring.text";  
 NSString *astring = [[NSString alloc] initWithContentsOfFile:path];  
 NSLog(@"astring:%@",astring);  
 [astring release];  

寫字串到檔案:writeToFile方法

 NSString *astring = [[NSString alloc] initWithString:@"This is a String!"];  
 NSLog(@"astring:%@",astring);  
 NSString *path = @"astring.text";      
 [astring writeToFile: path atomically: YES];  
 [astring release];      

比較兩個字串

1、用C比較:strcmp函式
 char string1[] = "string!";  
 char string2[] = "string!";  
 if(strcmp(string1, string2) = = 0)  
 {  
     NSLog(@"1");  
 }  
2、isEqualToString方法
 NSString *astring01 = @"This is a String!";  
 NSString *astring02 = @"This is a String!";  
 BOOL result = [astring01 isEqualToString:astring02];  
 NSLog(@"result:%d",result);  
3、compare方法(comparer返回的三種值)
 NSString *astring01 = @"This is a String!";  
 NSString *astring02 = @"This is a String!";      
 BOOL result = [astring01 compare:astring02] = = NSOrderedSame;      
 NSLog(@"result:%d",result);      
4、NSOrderedSame判斷兩者內容是否相同
 NSString *astring01 = @"This is a String!"; 
 NSString *astring02 = @"this is a String!";  
 BOOL result = [astring01 compare:astring02] = = NSOrderedAscending;      
 NSLog(@"result:%d",result);  
5、NSOrderedAscending判斷兩物件值的大小(按字母順序進行比較,astring02大於astring01為真)
  NSString *astring01 = @"this is a String!";  
  NSString *astring02 = @"This is a String!";  
  BOOL result = [astring01 compare:astring02] = = NSOrderedDescending;      
  NSLog(@"result:%d",result);       
6、NSOrderedDescending判斷兩物件值的大小(按字母順序進行比較,astring02小於astring01為真)
  • 不考慮大小寫比較字串1

    NSString *astring01 = @"this is a String!";  
    NSString *astring02 = @"This is a String!";  
    BOOL result = [astring01 caseInsensitiveCompare:astring02] = = NSOrderedSame;      
    NSLog(@"result:%d",result);
    
7、NSOrderedDescending判斷兩物件值的大小(按字母順序進行比較,astring02小於astring01為真)
  • 不考慮大小寫比較字串2

    NSString *astring01 = @"this is a String!";
    NSString *astring02 = @"This is a String!";  
    BOOL result = [astring01 compare:astring02 options:NSCaseInsensitiveSearch | NSNumericSearch] = = NSOrderedSame;      
    NSLog(@"result:%d",result);       
    

NSCaseInsensitiveSearch:不區分大小寫比較 NSLiteralSearch:進行完全比較,區分大小寫 NSNumericSearch:比較字串的字元個數,而不是字元值。

1、改變字串的大小寫
  NSString *string1 = @"A String";   
 NSString *string2 = @"String";   
 NSLog(@"string1:%@",[string1 uppercaseString]);//大寫  
 NSLog(@"string2:%@",[string2 lowercaseString]);//小寫  
 NSLog(@"string2:%@",[string2 capitalizedString]);//首字母大小  
2、在串中搜尋子串
 NSString *string1 = @"This is a string"; 
 NSString *string2 = @"string";  
 NSRange range = [string1 rangeOfString:string2];  
 int location = range.location;  
 int leight = range.length;  
 NSString *astring = [[NSString alloc] initWithString:[NSString stringWithFormat:@"Location:%i,Leight:%i",location,leight]];  
 NSLog(@"astring:%@",astring);  
 [astring release];  
3、抽取子串
-substringToIndex: 從字串的開頭一直擷取到指定的位置,但不包括該位置的字元
 NSString *string1 = @"This is a string";
 NSString *string2 = [string1 substringToIndex:3];
 NSLog(@"string2:%@",string2);
-substringFromIndex: 以指定位置開始(包括指定位置的字元),幷包括之後的全部字元
 NSString *string1 = @"This is a string";
 NSString *string2 = [string1 substringFromIndex:3];  
 NSLog(@"string2:%@",string2);  
-substringWithRange: //按照所給出的位置,長度,任意地從字串中擷取子串
 NSString *string1 = @"This is a string";  
 NSString *string2 = [string1 substringWithRange:NSMakeRange(0, 4)];  
 NSLog(@"string2:%@",string2);  
4、擴充套件路徑
 NSString *Path = @"~/NSData.txt";  
 NSString *absolutePath = [Path stringByExpandingTildeInPath];  
 NSLog(@"absolutePath:%@",absolutePath);  
 NSLog(@"Path:%@",[absolutePath stringByAbbreviatingWithTildeInPath]);  
5、副檔名
 NSString *Path = @"~/NSData.txt";  
 NSLog(@"Extension:%@",[Path pathExtension]);  

可變字串

1、給字串分配容量
stringWithCapacity:
 NSMutableString *String;  
 String = [NSMutableString stringWithCapacity:40];  
2、在已有字串後面新增字元
appendString: and appendFormat:
 NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];  
 //[String1 appendString:@", I will be adding some character"];  
 [String1 appendFormat:[NSString stringWithFormat:@", I will be adding some character"]]; 
 NSLog(@"String1:%@",String1);  
3、在已有字串中按照所給出範圍和長度刪除字元
 //deleteCharactersInRange:
 NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];  
 [String1 deleteCharactersInRange:NSMakeRange(0, 5)];  
 NSLog(@"String1:%@",String1);  
4、在已有字串後面在所指定的位置中插入給出的字串
 //-insertString: atIndex:  
 NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];  
 [String1 insertString:@"Hi! " atIndex:0];  
 NSLog(@"String1:%@",String1);  
5、將已有的空符串換成其它的字串
 //-setString:  
 NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];  
 [String1 setString:@"Hello Word!"];  
 NSLog(@"String1:%@",String1);  
6、按照所給出的範圍,和字串替換的原有的字元
 //-setString:  
 NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];  
 [String1 replaceCharactersInRange:NSMakeRange(0, 4) withString:@"That"];  
 NSLog(@"String1:%@",String1);  
7、判斷字串內是否還包含別的字串(字首,字尾)
01:檢查字串是否以另一個字串開頭- (BOOL) hasPrefix: (NSString *) aString;
 NSString *String1 = @"NSStringInformation.txt";  
 [String1 hasPrefix:@"NSString"] = = 1 ?  NSLog(@"YES") : NSLog(@"NO");  
 [String1 hasSuffix:@".txt"] = = 1 ?  NSLog(@"YES") : NSLog(@"NO");  
02:查詢字串某處是否包含其它字串 - (NSRange) rangeOfString: (NSString *) aString,這一點前面在串中搜尋子串用到過;

NSArray

建立數

 //NSArray *array = [[NSArray alloc] initWithObjects:
 @"One",@"Two",@"Three",@"Four",nil];  
 
 self.dataArray = array;  
 [array release];  
 
 //- (unsigned) Count;陣列所包含物件個數;  
 NSLog(@"self.dataArray cound:%d",[self.dataArray count]);  
 
 //- (id) objectAtIndex: (unsigned int) index;獲取指定索引處的物件;
 NSLog(@"self.dataArray cound 2:%@",[self.dataArray objectAtIndex:2]);  

從一個陣列拷貝資料到另一陣列(可變數級)

1、arrayWithArray:
 //NSArray *array1 = [[NSArray alloc] init];  
 NSMutableArray *MutableArray = [[NSMutableArray alloc] init];  
 NSArray *array = [NSArray arrayWithObjects: @"a",@"b",@"c",nil];  
 NSLog(@"array:%@",array);  
 MutableArray = [NSMutableArray arrayWithArray:array];  
 NSLog(@"MutableArray:%@",MutableArray);  
 array1 = [NSArray arrayWithArray:array];  
 NSLog(@"array1:%@",array1);  
2、Copy
 //id obj;  
 NSMutableArray *newArray = [[NSMutableArray alloc] init];  
 NSArray *oldArray = [NSArray arrayWithObjects: @"a",@"b",@"c",@"d",@"e",@"f",@"g",@"h",nil];  
 NSLog(@"oldArray:%@",oldArray);  
 for(int i = 0; i < [oldArray count]; i++)  
 {          
    obj = [[oldArray objectAtIndex:i] copy];  
    [newArray addObject: obj];  
 } 
 NSLog(@"newArray:%@", newArray);
 [newArray release];  
3、快速列舉
 //NSMutableArray *newArray = [[NSMutableArray alloc] init];  
 NSArray *oldArray = [NSArray arrayWithObjects:@"a",@"b",@"c",@"d",@"e",@"f",@"g",@"h",nil];      
 NSLog(@"oldArray:%@",oldArray);  
 for(id obj in oldArray)  
 {  
     [newArray addObject: obj];  
 }
  NSLog(@"newArray:%@", newArray); 
  [newArray release];      
4、Deep copy
 //NSMutableArray *newArray = [[NSMutableArray alloc] init];  
 NSArray *oldArray = [NSArray arrayWithObjects:  @"a",@"b",@"c",@"d",@"e",@"f",@"g",@"h",nil];
 NSLog(@"oldArray:%@",oldArray);      
 newArray = (NSMutableArray*)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, (CFPropertyListRef)oldArray, kCFPropertyListMutableContainers);  
  NSLog(@"newArray:%@", newArray);  
  [newArray release];      
5、Copy and sort
 //NSMutableArray *newArray = [[NSMutableArray alloc] init];
 NSArray *oldArray = [NSArray arrayWithObjects: @"b",@"a",@"e",@"d",@"c",@"f",@"h",@"g",nil];
 NSLog(@"oldArray:%@",oldArray);
 NSEnumerator *enumerator;
 enumerator = [oldArray objectEnumerator];
 id obj;
 while(obj = [enumerator nextObject])
 {
      [newArray addObject: obj]; 
 }
 [newArray sortUsingSelector:@selector(compare:)];
 NSLog(@"newArray:%@", newArray);
 [newArray release];  

切分陣列

1、從字串分割到陣列- componentsSeparatedByString:
 NSString *string = [[NSString alloc] initWithString:@"One,Two,Three,Four"];  
 NSLog(@"string:%@",string);      
 NSArray *array = [string componentsSeparatedByString:@","];  
 NSLog(@"array:%@",array);  
 [string release];  
2、從陣列合並元素到字串- componentsJoinedByString:
 NSArray *array = [[NSArray alloc] initWithObjects:@"One",@"Two",@"Three",@"Four",nil];  
 NSString *string = [array componentsJoinedByString:@","];
 NSLog(@"string:%@",string);  

NSMutableArray

給陣列分配容量

NSArray *array;
 array = [NSMutableArray arrayWithCapacity:20];  

在陣列末尾新增物件

- (void) addObject: (id) anObject;
 //NSMutableArray *array = [NSMutableArray arrayWithObjects: @"One",@"Two",@"Three",nil];
 [array addObject:@"Four"];
 NSLog(@"array:%@",array);  

刪除陣列中指定索引處物件

-(void) removeObjectAtIndex: (unsigned) index;
 //NSMutableArray *array = [NSMutableArray arrayWithObjects: @"One",@"Two",@"Three",nil];
 [array removeObjectAtIndex:1];
 NSLog(@"array:%@",array);  

陣列列舉

- (NSEnumerator *)objectEnumerator;從前向後
 //NSMutableArray *array = [NSMutableArray arrayWithObjects:  @"One",@"Two",@"Three",nil];
 NSEnumerator *enumerator;
 enumerator = [array objectEnumerator];
 
 id thingie;
 while (thingie = [enumerator nextObject]) {
     NSLog(@"thingie:%@",thingie);
  }  
- (NSEnumerator *)reverseObjectEnumerator;從後向前
 //NSMutableArray *array = [NSMutableArray arrayWithObjects: @"One",@"Two",@"Three",nil]; 
 NSEnumerator *enumerator; 
 enumerator = [array reverseObjectEnumerator];
 
 id object;
 while (object = [enumerator nextObject]) {
      NSLog(@"object:%@",object);
 }  

快速列舉

 //NSMutableArray *array = [NSMutableArray arrayWithObjects: @"One",@"Two",@"Three",nil];
 for(NSString *string in array
 {
    NSLog(@"string:%@",string);
 }  

NSDictionary

建立字典

- (id) initWithObjectsAndKeys;
 //NSDictionary *dictionary = [[NSDictionary alloc] initWithObjectsAndKeys:@"One",@"1",@"Two",@"2",@"Three",@"3",nil];
  NSString *string = [dictionary objectForKey:@"One"];
  NSLog(@"string:%@",string);
  NSLog(@"dictionary:%@",dictionary);
  [dictionary release];  

NSMutableDictionary

建立可變字典

1、建立
 NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];  
2、新增字典
 [dictionary setObject:@"One" forKey:@"1"];  
 [dictionary setObject:@"Two" forKey:@"2"];
 [dictionary setObject:@"Three" forKey:@"3"];
 [dictionary setObject:@"Four" forKey:@"4"];
 NSLog(@"dictionary:%@",dictionary);  
3、刪除指定的字典
 [dictionary removeObjectForKey:@"3"];
 NSLog(@"dictionary:%@",dictionary);  

NSValue(對任何物件進行包裝)

將NSRect放入NSArray中

1、將NSRect放入NSArray中
 NSMutableArray *array = [[NSMutableArray alloc] init];
 NSValue *value;
 CGRect rect = CGRectMake(0, 0, 320, 480);
 value = [NSValue valueWithBytes:&rect objCType:@encode(CGRect)];
 [array addObject:value];
 NSLog(@"array:%@",array);  
2、從Array中提取
 value = [array objectAtIndex:0];
 [value getValue:&rect];
 NSLog(@"value:%@",value);  
3、從目錄搜尋副檔名為jpg的檔案
 //NSFileManager *fileManager = [NSFileManager defaultManager];
 NSString *home;
 home = @"../Users/";
 
 NSDirectoryEnumerator *direnum;
 direnum = [fileManager enumeratorAtPath: home];
 
 NSMutableArray *files = [[NSMutableArray alloc] init];  
4、列舉
 NSString *filename;
 while (filename = [direnum nextObject]) { 
     if([[filename pathExtension] hasSuffix:@"jpg"]){
          [files addObject:filename];
          }
 }  
5、快速列舉
 for(NSString *filename in direnum)
 {
     if([[filename pathExtension] isEqualToString:@"jpg"]){
             [files addObject:filename];
             }  
 }
  NSLog(@"files:%@",files);  
4.1列舉
 NSEnumerator *filenum; 
 filenum = [files objectEnumerator]; 
 while (filename = [filenum nextObject]) {
     NSLog(@"filename:%@",filename);
 }  
5.1快速列舉
 for(id object in files) 
 {
     NSLog(@"object:%@",object);
 }  
 #import <Foundation/Foundation.h>
      int main (int argc, const char * argv[]) {
          NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
          //建立字串
          NSString *height;
          /**類方法:
           * +(id) stringWithFormat: (NSString *) format,...
           * 通過格式字串和引數來建立NSString
           * 省略號(。。。):可以接受多個以逗號分割的引數。
           * 這宣告方法時新增加號(+),那麼這個方法為類方法,不需要建立例項就可以呼叫,通常用於建立心的例項,我們稱用來建立新物件的類方法為工廠方法。
           * objective-c執行時生成一個類的時候,它會建立一個代表該類的類物件。類物件包含了指向超類的指標,類名,和指向類方法列表的指標。類物件還包含一個long型資料,為新建立的類例項物件指定大小(以位元組為單位)
           * 類方法可以用來訪問全域性資料。
           * 例項方法要用前導減號(-)來開始宣告
           */
         height=[NSString stringWithFormat:@"you heigh is %d feet,%d inches",5,11];
         NSLog(height);
         //length 返回字串中字元的個數。-(unsigned int) length;
         if([height length]>5){
             NSLog(@"height length ------");
         }
         //字串比較
         /**
          * isEqualToString :可以用來比較接收方和當作引數傳遞來的字串的內容是否相同,返回yes和no
          */
     NSString *thing1=@"hello";
     NSString *thing2=[[NSString alloc] initWithString:@"hello"];
     if([thing1 isEqualToString:thing2]){
         NSLog(@"they are same");
     }
     /**
      * ==:只判斷指標數值,而不是它們所指向的內容 
      */
      if(thing1==thing2){ 
         NSLog(@"== same");
      }
      
      /*
       * compare:比較兩個字串。區分大小寫
       * compare將接收物件和傳遞來的字串逐個字元的進行比較,它返回一個NSComparisonResult(列舉型別)來顯示結果。
       * typedef enum _NSComparisonResult{
       * NSOrderedAscending=-1;
       * NSOrderedsame;
       * NSOrderedDescending;
       * }
       * NSComparisonResult;
       */
    [thing1 compare:thing2];
    if(NSOrderedSame==[thing1 compare:thing2]){
       NSLog(@"compare same");
       
    } 
    
    //compare:options:
    /***
     * -(NSComparisonResult) compare:(NSString *) string
     * options:(unsinged) mask;
     *
     * options 是一個位掩碼,可以使用|新增選項標記
     * 選項:
     * NSCaseInsensitiveSearch:不區分大小寫字元
     * NSLiteralSearch:進行完全比較,區分大小寫
     * NSNumbericSearch:比較字串的字元個數,而不是字元值
     */
     
     if([thing1 compare:thing2 options:NSCaseInsensitiveSearch| NSNumericSearch]==NSOrderedSame)
     {
        NSLog(@"they match");
     }
     
     /** 
      * 以某個字串開始或結尾
      * -(BOOL) hasPrefix:(NSString *) aString;
      * -(BOOL) hasSuffix:(NSString *) aString;
      */
      
    NSString *fileName=@"aabbbcc";
    
    if([fileName hasPrefix:@"aa"])
    {
        NSLog(@"begin with aa");
    }
    
    if([fileName hasSuffix:@"cc"])
    {
       NSLog(@"end with cc");
    }
    
    //NSMutableString 可變字串
    //SString 是不可變的,一旦NSString 被建立了,我們就不能改變它。
    //+(id) stringWithCapacity:(unsinged) capacity; capacity:是給NSMutableString的一個建議,字串的大小並不侷限於所提供的大小,這個容量僅是個最優值。
    
    NSMutableString *str=[NSMutableString stringWithCapacity:40];
    [str appendFormat:@"sdfsdf%d",5];
    [str appendString:@"ssssssss"];
    NSLog(str);
    
    //刪除字串
    //-(void) deleteCharactersInRange:(NSRange) range;
    
    NSMutableString *ms;
    ms=[NSMutableString stringWithCapacity:50];
    [ms appendString:@"aabbccdd"];
    NSRange range;
    range=[ms rangeOfString:@"cc"];
    [ms deleteCharactersInRange:range];
     NSLog(ms);
     
     //與例項方法一樣,繼承對類方法也同樣適用
     
     //------------------集合--------------
     
     //NSArray ,NSDictionary
     /**
      * NSArray 是一個cocoa類,用來儲存物件的有序列表。
      * NSArray有兩個限制:1,它只能儲存objective-c的物件,而不能儲存c語言中的基本資料型別如int,float,enum,struct,或者nsarray中的隨機指標。2,不能這nsarray中儲存nil
      
      * 類方法:
      * arrayWithObjects:建立一個新的nsarray。傳送一個以逗號分割的物件列表,這列表結尾新增nil代表列表結束,(這就是不能這nsarray中儲存nil的原因)
      */
      
      NSArray *array=[NSArray arrayWithObjects:@"aa",@"bb",@"cc",nil];
      
      //-(unsigned) count; 取得包含物件的個數
      //-(id) objectAtIndex:(unsigned int) index; 取得索引位置的物件
      
      int i;
      for (i=0; i<[array count]; i++)
      {
        NSLog(@"index %d has %@",i,[array objectAtIndex:i]);
      }
      
      //------------切分陣列
      //-componentsSeparatedByString:
      NSString *ns=@"sdf,dsfs,dfd,fdf,df,dd";
      NSArray *comArr=[ns componentsSeparatedByString:@","];
      for(int i=0;i<[comArr count];i++){
         NSLog(@"componentsSeparatedByString===%@",[comArr objectAtIndex:i]);
       } 
       
       //componentJoinedByString: 合併nsarray中的元素來建立字串
       NSString *joinedStr=[comArr componentsJoinedByString:@"-->"];
       NSLog(@"joined---= %@",joinedStr);
       
       //可變陣列
       NSMutableArray *mutableArr=[NSMutableArray arrayWithCapacity:40];
       [mutableArr addObject:@"aa"];
       [mutableArr addObject:@"bb"];
       [mutableArr addObject:@"cc"];
       [mutableArr addObject:@"dd"];
       
       for(int i=0;i<[mutableArr count];i++)
       {
          NSLog(@"mutableArr==%@",[mutableArr objectAtIndex:i]);
          
       } 
       
       //-----  -(void) removeObjectAtIndex:(unsinged) index; 刪除指定索引的物件,
       //刪除一個物件之後,陣列中並沒有留下漏洞,被刪除物件後面的陣列元素的哦被前移來填補空缺 
       [mutableArr removeObjectAtIndex:2];
       for(int i=0;i<[mutableArr count];i++){
          NSLog(@"removeObjectAtIndex == %@",[mutableArr objectAtIndex:i]);
       } 
       
        //列舉
        //NSEnumerator ,它是cocoa用來描述這種集合迭代運輸的方法
        //-(NSEnumerator *) objectEnumerator;
        NSEnumerator *enumerator=[mutableArr objectEnumerator];
        id thingie;
        while(thingie=[enumerator nextObject])
        {
           NSLog(@"i found %@",thingie);
        }
        
         //快速列舉
         for(NSString *string in mutableArr){
            NSLog(@"for in == %@",string);
            
         }
         
         //NSDictionary 字典
         /*
          *  NSDictionary 是在給定的關鍵字(通常是一個NSString字串)下儲存一個數值(可以是任何型別的物件)。然後你可以用這個關鍵字來查詢相應的數值。
          *   NSDictionary 是鍵查詢的優化儲存方式。它可以立即找出要查詢的資料,而不需要遍歷整個陣列進行查詢。
          *   +(id) dictionaryWithObjectAndKeys:(id) firstObject,....; 
          *   該方法接收物件和關鍵字交替出現的系列,以nil值作為終止符號。
          */
           NSDictionary *dic=[NSDictionary dictionaryWithObjectsAndKeys:@"aaa",@"a",@"bbb",@"b",nil];
            NSString *dicStr=[dic objectForKey:@"a"];
            if([dicStr isEqualToString:@"aaa"]){
                NSLog(@"------------00000000000000000");
            }
            
            //可變字典
            NSMutableDictionary *mutableDic=[NSMutableDictionary dictionaryWithCapacity:50];
            [mutableDic setObject:@"1111" forKey:@"1"];
            [mutableDic setObject:@"222" forKey:@"2"]; 
            
            //刪除 -(void) removeObjectForKe:(id) key;
            [mutableDic removeObjectForKey:@"2"];
            
             NSArray *keyArr=[mutableDic allKeys];
             for(NSString *str in keyArr){
                NSLog(@"key== %@",str);
                NSLog(@"value== %@",[mutableDic objectForKey:str]);
             }
       //各種數值,NSNumber NSValue
       /*
        * cocoa 提供了NSNumber類來包裝基本資料型別
        * +(NSNumber *) numberWithChar:(char) value;
        * +(NSNumber *) numberWithInt:(int) value;
        * +(NSNumber *) numberWithFloat:(float) value;
        * +(NSNumber *) numberWthiBool:(BOOL) value;
        * -(char) charValue;
        * -(int) intVlaue;
        * -(float) floatValue;
        * -(BOOL) boolValue;
        * -(NSString *) stringValue;
        **/
    NSNumber *number;
    number=[NSNumber numberWithInt:3];
    [mutableDic setObject:number forKey:@"int"];
    
    int num=[[mutableDic objectForKey:@"int"] intValue];
    NSLog(@"int object value== %d",num);
    
    //NSValue .NSNumber實際上是NSValue的子類,NSValue可以包裝任意值
     /**
      * +(NSValue *) valueWithBytes:(const void *) value objCType:(const char *) type;
      * 傳遞的引數是你想要包裝的數值的地址,通常,得到的是你想要儲存的變數的地址(在c語言裡適用操作符 & ),你也可以提供一個描述這個資料型別的字串,通常用來說明struct中實體的型別和大小。你不用自己寫程式碼
      * 來生成這個字串,@encode編譯器指令可以接受資料型別的名稱併為你生成合適的字串
      */
   NSRect rect= NSMakeRect(1, 2, 30, 40);
   
   NSValue *value;
   value=[NSValue valueWithBytes:&rect objCType:@encode(NSRect)];
   NSMutableArray *mr=[NSMutableArray arrayWithCapacity:50];
   [mr addObject:value];
   
   //getValue 提取資料
   /**
    * -(void) getValue:(void *) value; 要傳遞的是儲存這個數值的變數的地址
    */
  
  /***
   * value=[mr objectAtIndex:0];
   * NSRect r;
   * NSLog(@"00000 ===%@",r);
   * [value getValue:&r];
   * NSLog(@"111== %@",r);
   */
 /** 
  * �+(NSValue *) valueWithPoint:(NSPoint) point;
  * +(NSValue *) valueWithSize:(NSSize) size;
  * +(NSValue *) valueWithRect:(NSRect) rect;

  * -(NSPoint) pointValue;
  * -(NSSize) sizeValue;
  * -(NSRect) rectValue; 
  */
 //NSNull
 /* 
  * +(NSNull *) null;
  */
 [mutableDic setObject:[NSNull null] forKey:@"fax"];
 id fax;
 fax=[mutableDic objectForKey:@"fax"];
 if(fax==[NSNull null]){
     NSLog(@"pppppppppppppppppp");
  }
  [pool drain];
  return 0;
  }  

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