ios 常用字符串的操作

//将NSData转化为NSString
NSString* str = [[NSString alloc] initWithData:response encoding:NSUTF8StringEncoding];
//将NSString 转化为NSData
(NSString.h)

  • (NSData *)dataUsingEncoding:(NSStringEncoding)encoding;

//载一个字符串中删除一个字符或字符串
[_display deleteCharactersInRange:NSMakeRange(index_of_char_to_remove, 1)];

数学转换为字符串
NSString *returnStr;
returnStr = [[NSNumber numberWithInt:row] stringValue];

 NSString  
 *******************************************************************************************/  
//一、NSString      
/*----------------创建字符串的方法----------------*/  
  
//1、创建常量字符串。  
NSString *astring = @"This is a String!";  
  
  
//2、创建空字符串,给予赋值。  
  
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、用标准c创建字符串:initWithCString方法  
  
char *Cstring = "This is a String!";  
NSString *astring = [[NSString alloc] initWithCString:Cstring];  
NSLog(@"astring:%@",astring);  
[astring release];  
  
  
  
//5、创建格式化字符串:占位符(由一个%加一个字符组成)  
  
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、创建临时字符串  
  
NSString *astring;  
astring = [NSString stringWithCString:"This is a temporary string"];  
NSLog(@"astring:%@",astring);  
  
  
  
  
/*----------------从文件读取字符串:initWithContentsOfFile方法----------------*/      
  
NSString *path = @"astring.text";  
NSString *astring = [[NSString alloc] initWithContentsOfFile:path];  
NSLog(@"astring:%@",astring);  
[astring release];  
  
  
/*----------------写字符串到文件: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];      
  
  
  
  
/*----------------比较两个字符串----------------*/          
  
//用C比较:strcmp函数  
  
char string1[] = "string!";  
char string2[] = "string!";  
if(strcmp(string1, string2) = = 0)  
{  
    NSLog(@"1");  
}  
  
  
  
//isEqualToString方法      
NSString *astring01 = @"This is a String!";  
NSString *astring02 = @"This is a String!";  
BOOL result = [astring01 isEqualToString:astring02];  
NSLog(@"result:%d",result);  
  
  
  
  
//compare方法(comparer返回的三种值)      
NSString *astring01 = @"This is a String!";  
NSString *astring02 = @"This is a String!";      
BOOL result = [astring01 compare:astring02] = = NSOrderedSame;      
NSLog(@"result:%d",result);      
//NSOrderedSame判断两者内容是否相同  
  
  
  
  
NSString *astring01 = @"This is a String!";  
NSString *astring02 = @"this is a String!";  
BOOL result = [astring01 compare:astring02] = = NSOrderedAscending;      
NSLog(@"result:%d",result);  
//NSOrderedAscending判断两对象值的大小(按字母顺序进行比较,astring02大于astring01为真)  
  
  
  
NSString *astring01 = @"this is a String!";  
NSString *astring02 = @"This is a String!";  
BOOL result = [astring01 compare:astring02] = = NSOrderedDescending;      
NSLog(@"result:%d",result);       
//NSOrderedDescending判断两对象值的大小(按字母顺序进行比较,astring02小于astring01为真)  
  
  
  
//不考虑大小写比较字符串1  
NSString *astring01 = @"this is a String!";  
NSString *astring02 = @"This is a String!";  
BOOL result = [astring01 caseInsensitiveCompare:astring02] = = NSOrderedSame;      
NSLog(@"result:%d",result);       
//NSOrderedDescending判断两对象值的大小(按字母顺序进行比较,astring02小于astring01为真)  
  
  
  
//不考虑大小写比较字符串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:不区分大小写比较 NSLiteralSearch:进行完全比较,区分大小写 NSNumericSearch:比较字符串的字符个数,而不是字符值。  
  
  
/*----------------改变字符串的大小写----------------*/      
  
NSString *string1 = @"A String";   
NSString *string2 = @"String";   
NSLog(@"string1:%@",[string1 uppercaseString]);//大写  
NSLog(@"string2:%@",[string2 lowercaseString]);//小写  
NSLog(@"string2:%@",[string2 capitalizedString]);//首字母大小  
  
  
/*----------------在串中搜索子串----------------*/          
  
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];  
  
  
/*----------------抽取子串 ----------------*/          
  
//-substringToIndex: 从字符串的开头一直截取到指定的位置,但不包括该位置的字符  
NSString *string1 = @"This is a string";  
NSString *string2 = [string1 substringToIndex:3];  
NSLog(@"string2:%@",string2);  
  
  
  
  
//-substringFromIndex: 以指定位置开始(包括指定位置的字符),并包括之后的全部字符  
NSString *string1 = @"This is a string";  
NSString *string2 = [string1 substringFromIndex:3];  
NSLog(@"string2:%@",string2);  
  
  
  
  
//-substringWithRange: //按照所给出的位置,长度,任意地从字符串中截取子串  
NSString *string1 = @"This is a string";  
NSString *string2 = [string1 substringWithRange:NSMakeRange(0, 4)];  
NSLog(@"string2:%@",string2);  
  
  
//扩展路径  
  
NSString *Path = @"~/NSData.txt";  
NSString *absolutePath = [Path stringByExpandingTildeInPath];  
NSLog(@"absolutePath:%@",absolutePath);  
NSLog(@"Path:%@",[absolutePath stringByAbbreviatingWithTildeInPath]);  
  
  
  
//文件扩展名  
NSString *Path = @"~/NSData.txt";  
NSLog(@"Extension:%@",[Path pathExtension]);  
  
  
  
  
/*******************************************************************************************  
 NSMutableString  
 *******************************************************************************************/      
  
/*---------------给字符串分配容量----------------*/  
//stringWithCapacity:  
NSMutableString *String;  
String = [NSMutableString stringWithCapacity:40];  
  
  
/*---------------在已有字符串后面添加字符----------------*/      
  
//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);  
*/  
  
  
/*--------在已有字符串中按照所给出范围和长度删除字符------*/      
/*  
 //deleteCharactersInRange:  
 NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];  
 [String1 deleteCharactersInRange:NSMakeRange(0, 5)];  
 NSLog(@"String1:%@",String1);  
  
  
  
 /*--------在已有字符串后面在所指定的位置中插入给出的字符串------*/  
  
//-insertString: atIndex:  
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];  
[String1 insertString:@"Hi! " atIndex:0];  
NSLog(@"String1:%@",String1);  
  
  
  
/*--------将已有的空符串换成其它的字符串------*/  
  
//-setString:  
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];  
[String1 setString:@"Hello Word!"];  
NSLog(@"String1:%@",String1);  
  
  
  
/*--------按照所给出的范围,和字符串替换的原有的字符------*/  
  
//-setString:  
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];  
[String1 replaceCharactersInRange:NSMakeRange(0, 4) withString:@"That"];  
NSLog(@"String1:%@",String1);  
  
  
  
/*-------------判断字符串内是否还包含别的字符串(前缀,后缀)-------------*/  
//01:检查字符串是否以另一个字符串开头- (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:查找字符串某处是否包含其它字符串 - (NSRange) rangeOfString: (NSString *) aString,这一点前面在串中搜索子串用到过;  
  
  
  
/*******************************************************************************************  
 NSArray  
 *******************************************************************************************/  
  
/*---------------------------创建数组------------------------------*/  
//NSArray *array = [[NSArray alloc] initWithObjects:  
@"One",@"Two",@"Three",@"Four",nil];  
  
self.dataArray = array;  
[array release];  
  
//- (unsigned) Count;数组所包含对象个数;  
NSLog(@"self.dataArray cound:%d",[self.dataArray count]);  
  
//- (id) objectAtIndex: (unsigned int) index;获取指定索引处的对象;  
NSLog(@"self.dataArray cound 2:%@",[self.dataArray objectAtIndex:2]);  
  
  
/*--------------------------从一个数组拷贝数据到另一数组(可变数级)----------------------------*/      
  
//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);  
  
  
//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];  
  
  
//快速枚举  
  
//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];      
  
  
//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];      
  
  
//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];  
  
  
  
/*---------------------------切分数组------------------------------*/  
  
//从字符串分割到数组- componentsSeparatedByString:  
NSString *string = [[NSString alloc] initWithString:@"One,Two,Three,Four"];  
NSLog(@"string:%@",string);      
NSArray *array = [string componentsSeparatedByString:@","];  
NSLog(@"array:%@",array);  
[string release];  
  
  
//从数组合并元素到字符串- componentsJoinedByString:  
NSArray *array = [[NSArray alloc] initWithObjects:@"One",@"Two",@"Three",@"Four",nil];  
NSString *string = [array componentsJoinedByString:@","];  
NSLog(@"string:%@",string);  
  
  
  
/*******************************************************************************************  
 NSMutableArray  
 *******************************************************************************************/  
/*---------------给数组分配容量----------------*/  
//NSArray *array;  
array = [NSMutableArray arrayWithCapacity:20];  
  
  
  
/*--------------在数组末尾添加对象----------------*/  
//- (void) addObject: (id) anObject;  
//NSMutableArray *array = [NSMutableArray arrayWithObjects:  
@"One",@"Two",@"Three",nil];  
[array addObject:@"Four"];  
NSLog(@"array:%@",array);  
  
  
  
/*--------------删除数组中指定索引处对象----------------*/      
//-(void) removeObjectAtIndex: (unsigned) index;      
//NSMutableArray *array = [NSMutableArray arrayWithObjects:  
@"One",@"Two",@"Three",nil];  
[array removeObjectAtIndex:1];  
NSLog(@"array:%@",array);  
  
  
  
/*-------------数组枚举---------------*/      
//- (NSEnumerator *)objectEnumerator;从前向后  
//NSMutableArray *array = [NSMutableArray arrayWithObjects:  
@"One",@"Two",@"Three",nil];  
NSEnumerator *enumerator;  
enumerator = [array objectEnumerator];  
  
id thingie;  
while (thingie = [enumerator nextObject]) {  
    NSLog(@"thingie:%@",thingie);  
}  
  
  
//- (NSEnumerator *)reverseObjectEnumerator;从后向前  
//NSMutableArray *array = [NSMutableArray arrayWithObjects:  
@"One",@"Two",@"Three",nil];  
NSEnumerator *enumerator;  
enumerator = [array reverseObjectEnumerator];  
  
id object;  
while (object = [enumerator nextObject]) {  
    NSLog(@"object:%@",object);  
}  
  
  
//快速枚举  
//NSMutableArray *array = [NSMutableArray arrayWithObjects:  
@"One",@"Two",@"Three",nil];  
for(NSString *string in array)  
{  
    NSLog(@"string:%@",string);  
}  
  
  
  
/*******************************************************************************************  
 NSDictionary  
 *******************************************************************************************/  
  
/*------------------------------------创建字典------------------------------------*/  
//- (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  
 *******************************************************************************************/  
  
/*------------------------------------创建可变字典------------------------------------*/      
//创建  
NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];  
  
//添加字典  
[dictionary setObject:@"One" forKey:@"1"];  
[dictionary setObject:@"Two" forKey:@"2"];  
[dictionary setObject:@"Three" forKey:@"3"];  
[dictionary setObject:@"Four" forKey:@"4"];  
NSLog(@"dictionary:%@",dictionary);  
  
//删除指定的字典  
[dictionary removeObjectForKey:@"3"];  
NSLog(@"dictionary:%@",dictionary);  
  
  
/*******************************************************************************************  
 NSValue(对任何对象进行包装)  
 *******************************************************************************************/  
  
/*--------------------------------将NSRect放入NSArray中------------------------------------*/      
//将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);  
  
//从Array中提取  
value = [array objectAtIndex:0];  
[value getValue:&rect];  
NSLog(@"value:%@",value);  
  
  
/*******************************************************************************************  
 从目录搜索扩展名为jpg的文件  
 *******************************************************************************************/  
  
//NSFileManager *fileManager = [NSFileManager defaultManager];  
NSString *home;  
home = @"../Users/";  
  
NSDirectoryEnumerator *direnum;  
direnum = [fileManager enumeratorAtPath: home];  
  
NSMutableArray *files = [[NSMutableArray alloc] init];  
  
//枚举  
NSString *filename;  
while (filename = [direnum nextObject]) {  
    if([[filename pathExtension] hasSuffix:@"jpg"]){  
        [files addObject:filename];  
    }  
}  
  
//快速枚举  
//for(NSString *filename in direnum)  
//{  
//    if([[filename pathExtension] isEqualToString:@"jpg"]){  
//        [files addObject:filename];  
//    }  
//}  
NSLog(@"files:%@",files);  
  
//枚举  
NSEnumerator *filenum;  
filenum = [files objectEnumerator];  
while (filename = [filenum nextObject]) {  
    NSLog(@"filename:%@",filename);  
}  
  
//快速枚举  
//for(id object in files)  
//{  
//    NSLog(@"object:%@",object);  
//}  







#import <Foundation/Foundation.h>  
  
int main (int argc, const char * argv[]) {  
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];  
    //创建字符串  
    NSString *height;  
    /**类方法:
     +(id) stringWithFormat: (NSString *) format,...
     通过格式字符串和参数来创建NSString
     省略号(。。。):可以接受多个以逗号分割的参数。
     这声明方法时添加加号(+),那么这个方法为类方法,不需要创建实例就可以调用,通常用于创建心的实例,我们称用来创建新对象的类方法为工厂方法。
     -------------------
     objective-c运行时生成一个类的时候,它会创建一个代表该类的类对象。类对象包含了指向超类的指针,类名,和指向类方法列表的指针。类对象还包含一个long型数据,为新创建的类实例对象指定大小(以字节为单位)
      
     类方法可以用来访问全局数据。
      
     实例方法要用前导减号(-)来开始声明
      
     */  
      
    height=[NSString stringWithFormat:@"you heigh is %d feet,%d inches",5,11];  
    NSLog(height);  
    //length 返回字符串中字符的个数。-(unsigned int) length;  
    if([height length]>5){  
        NSLog(@"height length ------");  
    }  
      
    //字符串比较  
    /**
     isEqualToString :可以用来比较接收方和当作参数传递来的字符串的内容是否相同,返回yes和no
     */  
    NSString *thing1=@"hello";  
    NSString *thing2=[[NSString alloc] initWithString:@"hello"];  
    if([thing1 isEqualToString:thing2]){  
        NSLog(@"they are same");      
    }  
    /**
     ==:只判断指针数值,而不是它们所指向的内容
     */  
    if(thing1==thing2){  
        NSLog(@"== same");  
    }  
      
    /*
     compare:比较两个字符串。区分大小写
     compare将接收对象和传递来的字符串逐个字符的进行比较,它返回一个NSComparisonResult(枚举类型)来显示结果。
     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 是一个位掩码,可以使用|添加选项标记
     选项:
     NSCaseInsensitiveSearch:不区分大小写字符
     NSLiteralSearch:进行完全比较,区分大小写
     NSNumbericSearch:比较字符串的字符个数,而不是字符值
     */  
    if([thing1 compare:thing2 options:NSCaseInsensitiveSearch|  
         NSNumericSearch]==NSOrderedSame){  
        NSLog(@"they match");  
    }  
      
    /**
     以某个字符串开始或结尾
     -(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 可变字符串  
    //SString 是不可变的,一旦NSString 被创建了,我们就不能改变它。  
      
    //+(id) stringWithCapacity:(unsinged) capacity; capacity:是给NSMutableString的一个建议,字符串的大小并不局限于所提供的大小,这个容量仅是个最优值。  
      
    NSMutableString *str=[NSMutableString stringWithCapacity:40];  
    [str appendFormat:@"sdfsdf%d",5];  
    [str appendString:@"ssssssss"];  
    NSLog(str);  
      
    //删除字符串  
    //-(void) deleteCharactersInRange:(NSRange) range;  
      
    NSMutableString *ms;  
    ms=[NSMutableString stringWithCapacity:50];  
    [ms appendString:@"aabbccdd"];  
    NSRange range;  
    range=[ms rangeOfString:@"cc"];  
    [ms deleteCharactersInRange:range];  
    NSLog(ms);  
      
    //与实例方法一样,继承对类方法也同样适用  
      
    //------------------集合--------------  
    //NSArray ,NSDictionary  
    /**
     NSArray 是一个cocoa类,用来存储对象的有序列表。
    NSArray有两个限制:1,它只能存储objective-c的对象,而不能存储c语言中的基本数据类型如int,float,enum,struct,或者nsarray中的随机指针。2,不能这nsarray中存储nil
      
     类方法:
     arrayWithObjects:创建一个新的nsarray。发送一个以逗号分割的对象列表,这列表结尾添加nil代表列表结束,(这就是不能这nsarray中存储nil的原因)
      
     */  
    NSArray *array=[NSArray arrayWithObjects:@"aa",@"bb",@"cc",nil];  
      
    //-(unsigned) count; 取得包含对象的个数  
    //-(id) objectAtIndex:(unsigned int) index; 取得索引位置的对象  
      
    int i;  
    for (i=0; i<[array count]; i++) {  
        NSLog(@"index %d has %@",i,[array objectAtIndex:i]);  
    }  
      
    //------------切分数组  
    //-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: 合并nsarray中的元素来创建字符串  
    NSString *joinedStr=[comArr componentsJoinedByString:@"-->"];  
    NSLog(@"joined---= %@",joinedStr);  
      
    //可变数组  
    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; 删除指定索引的对象,  
    //删除一个对象之后,数组中并没有留下漏洞,被删除对象后面的数组元素的哦被前移来填补空缺  
    [mutableArr removeObjectAtIndex:2];  
    for(int i=0;i<[mutableArr count];i++){  
        NSLog(@"removeObjectAtIndex == %@",[mutableArr objectAtIndex:i]);  
    }  
      
    //枚举  
    //NSEnumerator ,它是cocoa用来描述这种集合迭代运输的方法  
    //-(NSEnumerator *) objectEnumerator;  
    NSEnumerator *enumerator=[mutableArr objectEnumerator];  
    id thingie;  
    while(thingie=[enumerator nextObject]){  
        NSLog(@"i found %@",thingie);  
    }  
      
    //快速枚举  
    for(NSString *string in mutableArr){  
        NSLog(@"for in == %@",string);  
    }  
      
    //NSDictionary 字典  
    /*
     NSDictionary 是在给定的关键字(通常是一个NSString字符串)下存储一个数值(可以是任何类型的对象)。然后你可以用这个关键字来查找相应的数值。
     NSDictionary 是键查询的优化存储方式。它可以立即找出要查询的数据,而不需要遍历整个数组进行查找。
      
     +(id) dictionaryWithObjectAndKeys:(id) firstObject,....;
     该方法接收对象和关键字交替出现的系列,以nil值作为终止符号。
     **/  
    NSDictionary *dic=[NSDictionary dictionaryWithObjectsAndKeys:@"aaa",@"a",@"bbb",@"b",nil];  
    NSString *dicStr=[dic objectForKey:@"a"];  
    if([dicStr isEqualToString:@"aaa"]){  
        NSLog(@"------------00000000000000000");  
    }  
      
    //可变字典  
    NSMutableDictionary *mutableDic=[NSMutableDictionary dictionaryWithCapacity:50];  
    [mutableDic setObject:@"1111" forKey:@"1"];  
    [mutableDic setObject:@"222" forKey:@"2"];  
      
    //删除 -(void) removeObjectForKe:(id) key;  
    [mutableDic removeObjectForKey:@"2"];  
      
    NSArray *keyArr=[mutableDic allKeys];  
    for(NSString *str in keyArr){  
        NSLog(@"key== %@",str);  
        NSLog(@"value== %@",[mutableDic objectForKey:str]);  
    }  
      
      
    //各种数值,NSNumber NSValue  
    /*
     cocoa 提供了NSNumber类来包装基本数据类型
     +(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实际上是NSValue的子类,NSValue可以包装任意值  
      
    /**
     +(NSValue *) valueWithBytes:(const void *) value objCType:(const char *) type;
     传递的参数是你想要包装的数值的地址,通常,得到的是你想要存储的变量的地址(在c语言里适用操作符 & ),你也可以提供一个描述这个数据类型的字符串,通常用来说明struct中实体的类型和大小。你不用自己写代码
     来生成这个字符串,@encode编译器指令可以接受数据类型的名称并为你生成合适的字符串
     */  
    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 提取数据  
    /**
     -(void) getValue:(void *) value; 要传递的是存储这个数值的变量的地址
     */  
      
    /***
    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;  
}  
最后编辑于
©著作权归作者所有,转载或内容合作请联系作者
  • 序言:七十年代末,一起剥皮案震惊了整个滨河市,随后出现的几起案子,更是在滨河造成了极大的恐慌,老刑警刘岩,带你破解...
    沈念sama阅读 202,980评论 5 476
  • 序言:滨河连续发生了三起死亡事件,死亡现场离奇诡异,居然都是意外死亡,警方通过查阅死者的电脑和手机,发现死者居然都...
    沈念sama阅读 85,178评论 2 380
  • 文/潘晓璐 我一进店门,熙熙楼的掌柜王于贵愁眉苦脸地迎上来,“玉大人,你说我怎么就摊上这事。” “怎么了?”我有些...
    开封第一讲书人阅读 149,868评论 0 336
  • 文/不坏的土叔 我叫张陵,是天一观的道长。 经常有香客问我,道长,这世上最难降的妖魔是什么? 我笑而不...
    开封第一讲书人阅读 54,498评论 1 273
  • 正文 为了忘掉前任,我火速办了婚礼,结果婚礼上,老公的妹妹穿的比我还像新娘。我一直安慰自己,他们只是感情好,可当我...
    茶点故事阅读 63,492评论 5 364
  • 文/花漫 我一把揭开白布。 她就那样静静地躺着,像睡着了一般。 火红的嫁衣衬着肌肤如雪。 梳的纹丝不乱的头发上,一...
    开封第一讲书人阅读 48,521评论 1 281
  • 那天,我揣着相机与录音,去河边找鬼。 笑死,一个胖子当着我的面吹牛,可吹牛的内容都是我干的。 我是一名探鬼主播,决...
    沈念sama阅读 37,910评论 3 395
  • 文/苍兰香墨 我猛地睁开眼,长吁一口气:“原来是场噩梦啊……” “哼!你这毒妇竟也来了?” 一声冷哼从身侧响起,我...
    开封第一讲书人阅读 36,569评论 0 256
  • 序言:老挝万荣一对情侣失踪,失踪者是张志新(化名)和其女友刘颖,没想到半个月后,有当地人在树林里发现了一具尸体,经...
    沈念sama阅读 40,793评论 1 296
  • 正文 独居荒郊野岭守林人离奇死亡,尸身上长有42处带血的脓包…… 初始之章·张勋 以下内容为张勋视角 年9月15日...
    茶点故事阅读 35,559评论 2 319
  • 正文 我和宋清朗相恋三年,在试婚纱的时候发现自己被绿了。 大学时的朋友给我发了我未婚夫和他白月光在一起吃饭的照片。...
    茶点故事阅读 37,639评论 1 329
  • 序言:一个原本活蹦乱跳的男人离奇死亡,死状恐怖,灵堂内的尸体忽然破棺而出,到底是诈尸还是另有隐情,我是刑警宁泽,带...
    沈念sama阅读 33,342评论 4 318
  • 正文 年R本政府宣布,位于F岛的核电站,受9级特大地震影响,放射性物质发生泄漏。R本人自食恶果不足惜,却给世界环境...
    茶点故事阅读 38,931评论 3 307
  • 文/蒙蒙 一、第九天 我趴在偏房一处隐蔽的房顶上张望。 院中可真热闹,春花似锦、人声如沸。这庄子的主人今日做“春日...
    开封第一讲书人阅读 29,904评论 0 19
  • 文/苍兰香墨 我抬头看了看天上的太阳。三九已至,却和暖如春,着一层夹袄步出监牢的瞬间,已是汗流浃背。 一阵脚步声响...
    开封第一讲书人阅读 31,144评论 1 259
  • 我被黑心中介骗来泰国打工, 没想到刚下飞机就差点儿被人妖公主榨干…… 1. 我叫王不留,地道东北人。 一个月前我还...
    沈念sama阅读 42,833评论 2 349
  • 正文 我出身青楼,却偏偏与公主长得像,于是被迫代替她去往敌国和亲。 传闻我的和亲对象是个残疾皇子,可洞房花烛夜当晚...
    茶点故事阅读 42,350评论 2 342

推荐阅读更多精彩内容