iOS 字符串 数组 字典 操作!

常用的操作

enumerateKeysAndObjectsUsingBlock  字典遍历

 enumerateObjectsUsingBlock  数组遍历

characterAtIndex    substringWithRange    字符串遍历

 componentsSeparatedByString  字典转数组

//字典转json格式字符串：
- (NSString*)dictionaryToJson:(NSDictionary *)dic
{
    NSError *parseError = nil;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dic options:NSJSONWritingPrettyPrinted error:&parseError];

    return [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];  
}

//json格式字符串转字典：

- (NSDictionary *)dictionaryWithJsonString:(NSString *)jsonString {

    if (jsonString == nil) {

        return nil;

    }

    NSData *jsonData = [jsonString dataUsingEncoding:NSUTF8StringEncoding];

    NSError *err;

    NSDictionary *dic = [NSJSONSerialization JSONObjectWithData:jsonData

                                                        options:NSJSONReadingMutableContainers

                                                          error:&err];

    if(err) {

        NSLog(@"json解析失败：%@",err);

        return nil;

    }

    return dic;

}

 componentsSeparatedByString   按特定分割字符串转数组

 containsString  判断是否包含某个字符串

 allKeys    取出字典所有key (数组)

 allValues  取出字典所有Values (数组)

  [str substringToIndex:[self.pwd length]-1]   substringToIndex     截掉最后一个   substringFromIndex   截取最后一个  

  [str  stringByAppendingString:tags]     //字符串的追加,但是需要初始化字符串

 str =[strM stringByReplacingOccurrencesOfString:@"@2x.png" withString:@""];    //统一去掉后缀

 [str hasPrefix:@"https://"]    //判断字符串前缀    hasSuffix //后缀

字符串的操作

1. 创建一个新的空字符串

NSString *string1 = [NSString string];

 // C语言字符串
char *name = "hello word";
  // 初始化一个字符串，在赋值
 NSString *string2 = [[NSString alloc] init];
 string2 = @"wangchong";
 NSString *string3 = @"hello";
 // 一下两个方法是把字符串做一次拷贝,返回拷贝后的字符串
  NSString *string4 = [NSString stringWithString:@"hello"];
 NSString *string5 = [[NSString alloc] initWithString:string3];
 NSLog(@"%p,%p,%p",&string3,&string4,&string5);
 NSString *string6 = [string5 stringByAppendingString:@"
Hi"];
 // 把C的字符串转化为OC的字符串
    NSString *str = [[NSString alloc] initWithUTF8String:"hello world"];
    NSString *str2 = [NSString stringWithUTF8String:"hello world"];

  // 用格式化字符串初始化  可完成字符串的拼接以及完成C的字符串与OC的字符串的转化
    int a = 123;
    NSString *str3 = [[NSString alloc]initWithFormat:@"a = %d %s%@", a, "aaaa", @"bbbb"];
    NSString *str4 = [NSString stringWithFormat:@"%s","hello world"];

2.字符串的类型转换

    NSString * str = @"hello";
    const char *p = [str UTF8String]; // 将OC字符串转化为C的字符串

    str = @"123";
    int a = [str intValue]; // 将数字串转化成整型数据
    [str floatValue]; // 将数字串转化成float型
    [str doubleValue]; // 将数字串转化成double型

    // 结构体 输出
    // 结构体 [点] 转换字符串
    NSString *str1 = NSStringFromCGPoint(point);

    // 结构体 [尺寸] 转换字符串
    NSString *str2 = NSStringFromCGSize(size);

    // 结构体 [矩形] 转换字符串
    NSString *str3 = NSStringFromCGRect(rect);

3.字符串大小写转换

 // 全部转为大写 结果 ABC
    [@"abc" uppercaseString];
    // 全部转为小写 结果 bcd
    [@"BCD" lowercaseString];
    // 首字母大写 结果 Acb
    [@"acb" capitalizedString];

4.字符串比较

   // 比较两个字符串内容是否相同
    // 相等返回 yes 不相等返回 no
    BOOL b =[str isEqualToString:str2];

    //判断str2中是否包含str1
    [str2 containsString:str1];
    // 忽略大小写进行比较
    NSComparisonResult  result1 = [string caseInsensitiveCompare:str];
    NSComparisonResult  result2 = [string localizedCaseInsensitiveCompare:str];

    // 两个字符串内容比较
    // NSComparisonResult result = {NSOrderedAscending, NSOrderedSame，NSOrderedDescending}
    // NSOrderedAscending    右边 > 左边  == -1
    // NSOrderedSame         内容相同     ==  0
    // NSOrderedDescending   左边 > 右边  ==  1

    NSComparisonResult result3 = [str compare:str2];
    NSComparisonResult result4 = [string compare:@"taojian" options:NSCaseInsensitiveSearch];
    NSComparisonResult result5 = [string compare:@"taojian" options:NSCaseInsensitiveSearch range:NSMakeRange(0, string.length)];
    NSComparisonResult result6 = [string compare:@"taojian" options:NSCaseInsensitiveSearch range:NSMakeRange(0, string.length) locale:nil];
    NSComparisonResult result7 = [string localizedCompare:str];

options: // 枚举参数
    enum{
        NSCaseInsensitiveSearch = 1, // 不区分大小写比较
        NSLiteralSearch = 2, // 区分大小写比较
        NSBackwardsSearch = 4, // 从字符串末尾开始搜索
        NSAnchoredSearch = 8, // 搜索限制范围的字符串
        NSNumbericSearch = 64 // 按照字符串里的数字为依据，算出顺序。例如 Foo2.txt < Foo7.txt < Foo25.txt

        // 以下定义高于 mac os 10.5 或者高于 iphone 2.0 可用    ,
        NSDiacriticInsensitiveSearch = 128, // 忽略 "-" 符号的比较
        NSWidthInsensitiveSearch = 256, // 忽略字符串的长度，比较出结果
        NSForcedOrderingSearch = 512 // 忽略不区分大小写比较的选项，并强制返回 NSOrderedAscending 或者 NSOrderedDescending

        // 以下定义高于 iphone 3.2 可用    ,
        /// 只能应用于 rangeOfString:..., stringByReplacingOccurrencesOfString:...和 replaceOccurrencesOfString:... 方法。
        /// 使用通用兼容的比较方法，如果设置此项，可以去掉 NSCaseInsensitiveSearch 和 NSAnchoredSearc
        NSRegularExpressionSearch = 1024

5.字符串搜索

  // 判断字符串是否以abc开头
    [@"abcdfa" hasPrefix:@"abc"];
    // 判断字符串是否bcd结尾
    [@"adbcd" hasSuffix:@"bcd"];
    // 判断字符串是否包含指定字符串，返回位置和长度
    NSRange range = [@"123456" rangeOfString:@"456"];
    // 搜索字符串所在的范围
    NSRange range = [@"123456456qweasasd456" rangeOfString:@"456" options:NSBackwardsSearch];  // 输出{17, 3}
    // 指定范围进行搜索
    NSRange range = NSMakeRange(0, 9);
    range = [@"123456456qweasasd456" rangeOfString:@"456" options:NSBackwardsSearch range:range];
    // 找与之开头相同的字符 返回相同开头的字符串
        NSString *string = @"fg   s  abcdefg hijklmn s     d 
 fdsgf";
    NSString *str = [string commonPrefixWithString:@"fgsdfgrg" options:NSLiteralSearch]; // 输出fg

6.字符串截取

    NSString * str5 = @"helloworld";
    NSString * ptr1 = [str5 substringToIndex:2];// 字符串抽取 从头开始抽取2个字母,返回he
    NSString * ptr2 = [str5 substringFromIndex:4];// 从第4个字母开始抽取到字符串结束,返回oworld
    NSRange range1 = {6,2};// 结构体初始化
    NSString * ptr3 = [str5 substringWithRange:range1];// 在range指定范围内抽取,返回or
    NSString * ptr4 = [str5 substringWithRange:NSMakeRange(6,2)];// NSMakeRange可以生成一个结构体

 // 取出字符串"123-456-789-000"中的数字部分,组成一个新的字符串输出
    NSMutableString *strm = [NSMutableString stringWithString:@"123-456-789-000"]; //只有可变字符串有这个方法
    [strm replaceOccurrencesOfString:@"-"
                          withString:@""
                             options:NSLiteralSearch
                               range:NSMakeRange(0, strm.length)];
    NSLog(@"%@",strm);  //输出:123456789000

   //    substringToIndex     截掉最后一个 //    substringFromIndex   截取最后一个  

   [str substringToIndex:[self.pwd length]-1]

   //字符串的追加,但是需要初始化字符串

   [str  stringByAppendingString:tags] 

  //统一去掉后缀

  str =[strM stringByReplacingOccurrencesOfString:@"@2x.png" withString:@""];

  //判断字符串前缀    hasSuffix //后缀

 [str hasPrefix:@"https://"]

7.字符串的遍历

// 根据
遍历
NSString *string = @"   s  abcdefg hijklmn s     d 
 fdsf";
// 根据
一行一行的打印
[string enumerateLinesUsingBlock:^(NSString *line, BOOL *stop){
                                      NSLog(@"
%@",line);
     }
];

// 根据 条件options 遍历
NSString *string = @"   s  abcdefg hijklmn s     d ";
NSMutableString * mutableString = [NSMutableString string];
// NSStringEnumerationByWords：将string按空格分开，并且会自动清理首尾的空格
// 这个方法会把中间多余的空格也清理掉，比如上面的字符串，s和d之间有两个空格，会变成一个空格
[string enumerateSubstringsInRange:NSMakeRange(0, string.length) options:NSStringEnumerationByWords usingBlock:
^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop)
{
        [mutableString appendFormat:@"%@ ",substring];
}];

// 删除我们添加的末尾的一个空格
[mutableString deleteCharactersInRange:NSMakeRange(outputString.length-1, 1)];

8.路径操作与数组操作

// 用指定字符串分割字符串，返回一个数组   
NSArray *array = [@"1,2,3,4,5,6" componentsSeparatedByString:@","];  

// 根据空格拆分
NSArray *array = [string componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]]; 

// 将数组中的字符串组合成一个文件路径   
NSMutableArray *components = [NSMutableArray array];  
[components addObject:@"Users"];  
[components addObject:@"CentralPerk"];  
[components addObject:@"Desktop"];  
NSString *path = [NSString pathWithComponents:components];  
NSLog(@"%@",path);  //Users/CentralPerk/Desktop   

// 将一个路径分割成一个数组   
NSArray *array1 = [path pathComponents];  
NSLog(@"%@",array1);

// 判断是否为绝对路径(依据：是否以'/'开始)   
path = @"/Users/CentralPerk/Desktop";  
NSLog(@"%i",[path isAbsolutePath]);  

// 获取最后一个目录   
NSLog(@"%@",[path lastPathComponent]);  

// 删除最后一个目录   
NSLog(@"%@",[path stringByDeletingLastPathComponent]);  

// 拼接一个目录   
NSLog(@"%@",[path stringByAppendingPathComponent:@"aaa"]);   //Users/CentralPerk/Desktop/aaa   
NSLog(@"%@",[path stringByAppendingString:@"aaa"]);      //Users/CentralPerk/Desktopaaa   
NSLog(@"%@",[path stringByAppendingFormat:@"%@%@",@"b",@"c"]);  //Users/CentralPerk/Desktopbc

9.文件扩展名

// 拓展名出来   
 // 获取拓展名,不带.   
 NSString *str2 = @"Users/CentralPerk/Desktop/test.txt";  
 NSLog(@"%@",[str2 pathExtension]);  
 // 添加拓展名,不需要带.   
 NSLog(@"%@",[str2 stringByAppendingPathExtension:@"mp3"]);  
 // 删除拓展名,带.一块删除   
 NSLog(@"%@",[str2 stringByDeletingPathExtension]);

10.文件操作

// 将字符串设置为path制定的文件的内容 
-(id) initWithContentsOfFile:path encoding:enc error:err  
// 创建一个新字符串并将其设置为path指定的文件的内容，使用字符编码enc，如果非零，则返回err中错误  
+(id) stringWithContentsOfFile:path encoding:enc error:err  


// 将字符串设置为url(NSURL *)url的内容，使用字符编码enc，如果非零，则返回err中的错误 
-(id) initWithContentsOfURL:url encoding:enc error:err   
// 创建一个新的字符串，并将其设置为url的内容，使用字符编码enc，如果非零，则返回err中的错误 
+(id) stringWithContentsOfURL:url encoding:enc error:err

11.补充

// 求字符串长度 
[str1 length]   
// 获取字符串中的字符 
[str1 characterAtIndex:1]
// 清楚左右两段的空格
NSString *str = [string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
// 在字符串后面补0
NSString *str = [string stringByPaddingToLength:12 withString:@"0" startingAtIndex:0];

二、NSMutableString

// 将不可变的字符串转换为可变的字符串 
NSMutableString * str =  [[NSMutableString alloc]initWithString:@"hello world"];

// 在指定下标为2的(不要越界)位置插入013字符串
[str insertString:@"013" atIndex:2]; 

// 在字符串末尾追加字符串taotao 
[str appendString:@"taotao"];

// 从0位置删除2个字符 
[str deleteCharactersInRange:NSMakeRange(0, 2)];

// 给字符串重新赋值 
[str setString:@"yintian"];

// 将3位置后1个字符替换成ios字符串
[str replaceCharactersInRange:NSMakeRange(3, 1) withString:@"ios"];

// 根据选项 opts ，使用指定 range 中的nsstring2 替换所有的 nsstring
-(void)replaceOccurrencesOfString:nsstring withString:nsstring2 options:opts range:range

 数组操作!

int count = [array count];//个数  
// 判断是否包含了某个元素  
if ([array containsObject:@"a"]) {  
    NSLog(@"包含了字符串a");  
}  
NSString *last = [array lastObject];最后一个元素  
NSString *str = [array objectAtIndex:1];根据索引获取数组中的元素  
int index = [array indexOfObject:@"c"];获取指定元素的索引  
// 让数组里面的所有对象都调用test方法，123为参数  
NSArray *array = [NSArray arrayWithObjects:stu1, stu2, stu3, nil nil];  
[array makeObjectsPerformSelector:@selector(test2:) withObject:@"123"];  
NSArray *array = [NSArray arrayWithObjects:@"1", @"2", @"3", @"4", nil nil];  
// 1-2-3-4  
// 利用分隔符-拼接所有的数组元素  
NSString *str = [array componentsJoinedByString:@"-"];  
// 将一个数组写入文件（生成的是一个xml文件）  
NSString *path = @"/Users/apple/Desktop/array.xml";  
[array writeToFile:path atomically:YES];  
path = @"/Users/apple/Desktop/array.txt";  
// 从文件中读取数组内容（文件有严格的格式要求）  
NSArray *array2 = [NSArray arrayWithContentsOfFile:path];  

#pragma mark 遍历数组1  
void arrayFor1() {  
    NSArray *array = [NSArray arrayWithObjects:stu1, @"1", @"2", @"3", nil nil];  
    int count = array.count;  
    for (int i = 0; i<count; i++) {  
        id obj = [array objectAtIndex:i];  
    }  
}  
  
#pragma mark 遍历数组2 快速遍历  
void arrayFor2() {  
    Student *stu1 = [Student student];  
    NSArray *array = [NSArray arrayWithObjects:stu1, @"1", @"2", @"3", nil nil];  
    int i =0;  
    for (id obj in array) {  
        NSLog(@"%i-%@", i, obj);  
        i++;  
    }  
}  
  
#pragma mark 遍历数组3  
void arrayFor3() {  
    Student *stu1 = [Student student];  
    NSArray *array = [NSArray arrayWithObjects:stu1, @"1", @"2", @"3", nil nil];  
    [array enumerateObjectsUsingBlock:  
     ^(id obj, NSUInteger idx, BOOLBOOL *stop) {  
        NSLog(@"%i-%@", idx, obj);  
         // 如果索引为1，就停止遍历  
         if (idx == 1) {  
             // 利用指针修改外面BOOL变量的值  
             *stop = YES;  
         }  
    }];  
}  
  
#pragma mark 遍历数组4  
void arrayFor4() {  
    Student *stu1 = [Student student];  
    NSArray *array = [NSArray arrayWithObjects:stu1, @"1", @"2", @"3", nil nil];  
    // 获取数组的迭代器  
    // NSEnumerator *enumerator = [array objectEnumerator];  
    // 反序迭代器（从尾部开始遍历元素）  
    NSEnumerator *enumerator = [array reverseObjectEnumerator];  
    // allObjects是取出没有被遍历过的对象  
    NSArray *array2 = [enumerator allObjects];  
    NSLog(@"array2:%@", array2);  
    // 获取下一个需要遍历的元素  
    id obj = nil;  
    while (obj = [enumerator nextObject]) {  
        NSLog(@"obj=%@", obj);  
    }  
}  

#pragma mark 数组排序1  
void arraySort1() {  
    NSArray *array = [NSArray arrayWithObjects:@"2", @"3", @"1", @"4", nil nil];  
      
    // 返回一个排好序的数组，原来数组的元素顺序不会改变  
    // 指定元素的比较方法：compare:  
    NSArray *array2 = [array sortedArrayUsingSelector:@selector(compare:)];  
    NSLog(@"array2:%@", array2);  
}  
  
#pragma mark 数组排序2  
void arraySort2() {  
    Student *stu1 = [Student studentWithFirstname:@"MingJie" lastname:@"Li"];  
    Student *stu2 = [Student studentWithFirstname:@"LongHu" lastname:@"Huang"];  
    Student *stu3 = [Student studentWithFirstname:@"LianJie" lastname:@"Li"];  
    Student *stu4 = [Student studentWithFirstname:@"Jian" lastname:@"Xiao"];  
    NSArray *array = [NSArray arrayWithObjects:stu1,stu2,stu3, stu4, nil nil];  
    // 指定排序的比较方法  
    NSArray *array2 = [array sortedArrayUsingSelector:@selector(compareStudent:)];  
    NSLog(@"array2:%@", array2);  
}  
- (NSComparisonResult)compareStudent:(Student *)stu {  
    // 先按照姓排序  
    NSComparisonResult result = [self.lastname compare:stu.lastname];  
    // 如果有相同的姓，就比较名字  
    if (result == NSOrderedSame) {  
        result = [self.firstname compare:stu.firstname];  
    }  
    return result;  
}  
  
#pragma mark 数组排序3  
void arraySort3() {  
    Student *stu1 = [Student studentWithFirstname:@"MingJie" lastname:@"Li"];  
    Student *stu2 = [Student studentWithFirstname:@"LongHu" lastname:@"Huang"];  
    Student *stu3 = [Student studentWithFirstname:@"LianJie" lastname:@"Li"];  
    Student *stu4 = [Student studentWithFirstname:@"Jian" lastname:@"Xiao"];  
    NSArray *array = [NSArray arrayWithObjects:stu1,stu2,stu3, stu4, nil nil];  
      
    // 利用block进行排序  
    NSArray *array2 = [array sortedArrayUsingComparator:  
     ^NSComparisonResult(Student *obj1, Student *obj2) {  
         // 先按照姓排序  
         NSComparisonResult result = [obj1.lastname compare:obj2.lastname];  
         // 如果有相同的姓，就比较名字  
         if (result == NSOrderedSame) {  
             result = [obj1.firstname compare:obj2.firstname];  
         }  
           
         return result;  
    }];  
      
    NSLog(@"array2:%@", array2);  
}  
  
#pragma mark 数组排序4-高级排序  
void arraySort4() {  
    Student *stu1 = [Student studentWithFirstname:@"MingJie" lastname:@"Li" bookName:@"book1"];  
    Student *stu2 = [Student studentWithFirstname:@"LongHu" lastname:@"Huang" bookName:@"book2"];  
    Student *stu3 = [Student studentWithFirstname:@"LianJie" lastname:@"Li" bookName:@"book2"];  
    Student *stu4 = [Student studentWithFirstname:@"Jian" lastname:@"Xiao" bookName:@"book1"];  
    NSArray *array = [NSArray arrayWithObjects:stu1,stu2,stu3, stu4, nil nil];  
      
    // 1.先按照书名进行排序  
    // 这里的key写的是@property的名称  
    NSSortDescriptor *bookNameDesc = [NSSortDescriptor sortDescriptorWithKey:@"book.name" ascending:YES];  
    // 2.再按照姓进行排序  
    NSSortDescriptor *lastnameDesc = [NSSortDescriptor sortDescriptorWithKey:@"lastname" ascending:YES];  
    // 3.再按照名进行排序  
    NSSortDescriptor *firstnameDesc = [NSSortDescriptor sortDescriptorWithKey:@"firstname" ascending:YES];  
    // 按顺序添加排序描述器  
    NSArray *descs = [NSArray arrayWithObjects:bookNameDesc, lastnameDesc, firstnameDesc, nil nil];  
      
    NSArray *array2 = [array sortedArrayUsingDescriptors:descs];  
      
    NSLog(@"array2:%@", array2);  
} 

字典操作

//创建词典
    NSDictionary *dictionary=[NSDictionary dictionaryWithObjectsAndKeys:@"wujy",@"name",@29,@"age",nil];
    NSInteger Count=[dictionary count];
    NSLog(@"词典的个数为%ld",Count);
    
    //得到词典中的所有key
    NSEnumerator *enumeratorkey=[dictionary keyEnumerator];
    for (NSObject *obj in enumeratorkey) {
        NSLog(@"key为：%@",obj);
        NSLog(@"通过key找到value值为：%@",[dictionary objectForKey:obj]);
    }
    
    //得到词典中的所有value值
    NSEnumerator *enumeratorvalue=[dictionary objectEnumerator];
    for (NSObject *obj in enumeratorvalue) {
        NSLog(@"value为：%@",obj);
    }
    
    //简便的方式创建 key排前面value排后面
    NSDictionary *newDictionary=@{@"name":@"wujy",@"age":@29};
    NSArray *keyArray=[newDictionary allKeys];
    for (NSObject *obj in keyArray) {
        NSLog(@"key的值为：%@",obj);
    }
    
    NSArray *valueArray=[newDictionary allValues];
    for (NSObject *obj in valueArray) {
        NSLog(@"value的值为：%@",obj);
    }
    
    //blocks插件
    NSDictionary *blockDictionary=[NSDictionary dictionaryWithObjects:[[NSArray alloc] initWithObjects:@3,@15,@29,nil] forKeys:[[NSArray alloc] initWithObjects:@"IOS",@"work",@"age",nil]];
    //遍历
    [blockDictionary bk_each:^(id key, id obj) {
        NSLog(@"使用blocks的key为:%@",key);
        NSLog(@"对应的value为:%@",obj);
    }];
    
    //过滤 只在第一个符合条件时就停止

    NSDictionary *matchDictionary=[blockDictionary bk_match:^BOOL(id key, id obj) {

        BOOL select=[obj intValue]<10?YES:NO;
        return select;
    }];
    NSLog(@"match符合的项为：%@",matchDictionary);
    
    //过滤
    NSDictionary *selectDictionary=[blockDictionary bk_select:^BOOL(id key, id obj) {
        BOOL select=[obj intValue]>10?YES:NO;
        return select;
    }];
    NSLog(@"select符合的项为%@",selectDictionary);
    
    //反向过滤
    NSDictionary *rejectDictionary=[blockDictionary bk_reject:^BOOL(id key, id obj) {
        BOOL select=[obj intValue]>10?YES:NO;
        return select;
    }];
    NSLog(@"reject符合的项为%@",rejectDictionary);
    
    //对各个项进行修改
    NSDictionary *mapDictinary=[blockDictionary bk_map:^id(id key, id obj) {
        return [NSNumber numberWithInt:[obj intValue]+1];
    }];
    NSLog(@"map修改后的项为%@",mapDictinary);
    
    //是否符合条件 返回bool
    BOOL isSelected=[blockDictionary bk_any:^BOOL(id key, id obj) {
        BOOL select=[obj intValue]>20?YES:NO;
        return select;
    }];
    NSLog(@"%d符合条件",isSelected);
    
    //判断是否所有的项都符合这个条件
    BOOL allSelected=[blockDictionary bk_all:^BOOL(id key, id obj) {
        BOOL select=[obj intValue]>20?YES:NO;
        return select;
    }];
    NSLog(@"%d符合条件",allSelected);
    
    //判断是否所有的项都不符合这个条件
    BOOL noneSelected=[blockDictionary bk_none:^BOOL(id key, id obj) {
        BOOL select=[obj intValue]>50?YES:NO;
        return select;
    }];
    NSLog(@"%d符合条件",noneSelected);

//创建一个nsmutabledictionary
    NSMutableDictionary *mutableDictionary=[NSMutableDictionary dictionaryWithCapacity:3];
    [mutableDictionary setObject:@"wujy" forKey:@"name"];
    [mutableDictionary setObject:@"cnblogs.com/wujy" forKey:@"webName"];
    [mutableDictionary setObject:@29 forKey:@"age"];
    
    //得到词典中的所有key
    NSEnumerator *enumeratorkey=[mutableDictionary keyEnumerator];
    for (NSObject *obj in enumeratorkey) {
        NSLog(@"key为：%@",obj);
        NSLog(@"通过key找到value值为：%@",[mutableDictionary objectForKey:obj]);
    }
    
    //删除其中一个key
    [mutableDictionary removeObjectForKey:@"name"];
    NSLog(@"删除name的key以后值：%@",mutableDictionary);
    
    [mutableDictionary removeAllObjects];
    NSLog(@"删除所有以后，可变词典个数为%ld",[mutableDictionary count]);
    
    //blocks
    //过滤
    NSMutableDictionary *newmutableDictionary=[NSMutableDictionary dictionaryWithDictionary:@{@"IOS":@3,@"work":@13,@"age":@29}];
    [newmutableDictionary bk_performSelect:^BOOL(id key, id obj) {
        BOOL select=[obj intValue]>10?YES:NO;
        return select;
    }];
    NSLog(@"过滤后的可变词典为(29,13)%@",newmutableDictionary);
    
    //取反过滤
    [newmutableDictionary bk_performReject:^BOOL(id key, id obj) {
        BOOL select=[obj intValue]>20?YES:NO;
        return select;
    }];
    NSLog(@"取反过滤的可变词典为(13)%@",newmutableDictionary);
    
    //修改各个项的结果
    [newmutableDictionary bk_performMap:^id(id key, id obj) {
        return @([obj intValue]+1);
    }];
    NSLog(@"修改后的可变词典为(14)%@",newmutableDictionary);