程序師世界是廣大編程愛好者互助、分享、學習的平台,程序師世界有你更精彩!
首頁
編程語言
C語言|JAVA編程
Python編程
網頁編程
ASP編程|PHP編程
JSP編程
數據庫知識
MYSQL數據庫|SqlServer數據庫
Oracle數據庫|DB2數據庫
 程式師世界 >> 編程語言 >> C語言 >> 關於C語言 >> Objective-c史上最全字符串處理

Objective-c史上最全字符串處理

編輯:關於C語言

//將NSData轉化為NSString
NSString* str = [[NSString alloc] initWithData:response encoding:NSUTF8StringEncoding];
//將NSString 轉化為NSData
(NSString.h)
- (NSData *)dataUsingEncoding:(NSStringEncoding)encoding;



//載一個字符串中刪除一個字符或字符串
[_display deleteCharactersInRange:NSMakeRange(index_of_char_to_remove, 1)];

數學轉換為字符串
NSString *returnStr;
returnStr = [[NSNumber numberWithInt:row] stringValue];



int轉為NSString
for (int Abb_Appid=500001; Abb_Appid<500012; Abb_Appid++) {
NSString *Abb_AppID_ID=[NSString stringWithFormat:@"%d",Abb_Appid];
}


NSString *tempA = @"123";
NSString *tempB = @"456";
1,字符串拼接
NSString *newString = [NSString stringWithFormat:@"%@%@",tempA,tempB];
2,字符轉int
int intString = [newString intValue];
3,int轉字符
NSString *stringInt = [NSString stringWithFormat:@"%d",intString];
4,字符轉float
float floatString = [newString floatValue];
5,float轉字符
NSString *stringFloat = [NSString stringWithFormat:@"%f",intString];

NSString
*******************************************************************************************/
//一、NSString
/*----------------創建字符串的方法----------------*/

//1、創建常量字符串。
NSString *astring = @"This is a String!";


//2、創建空字符串,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、用標准c創建字符串:initWithCString方法

char *Cstring = "This is a String!";
NSString *astring = [[NSString alloc] initWithCString:Cstring];
NSLog(@"astring:%@",astring);
[astring release];



//5、創建格式化字符串:占位符(由一個%加一個字符組成)

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、創建臨時字符串

NSString *astring;
astring = [NSString stringWithCString:"This is a temporary string"];
NSLog(@"astring:%@",astring);




/*----------------從文件讀取字符串:initWithContentsOfFile方法----------------*/

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


/*----------------寫字符串到文件: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];




/*----------------比較兩個字符串----------------*/

//用C比較:strcmp函數

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返回的三種值)
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);
//NSOrderedAscending判斷兩對象值的大小(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);
//NSOrderedDescending判斷兩對象值的大小(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判斷兩對象值的大小(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:不區分大小寫比較 NSLiteralSearch:進行完全比較,區分大小寫 NSNumericSearch:比較字符串的字符個數,而不是字符值。


/*----------------改變字符串的大小寫----------------*/

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


/*----------------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: 從字符串的開頭一直截取到指定的位置,但不包括該位置的字符
NSString *string1 = @"This is a string";
NSString *string2 = [string1 substringToIndex:3];
NSLog(@"string2:%@",string2);




//-substringFromIndex: 以指定位置開始(包括指定位置的字符),並包括之後的全部字符
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,任意地從字符串中截取子串
NSString *string1 = @"This is a string";
NSString *string2 = [string1 substringWithRange:NSMakeRange(0, 4)];
NSLog(@"string2:%@",string2);


//擴展路徑

NSString *Path = @"~/NSData.txt";
NSString *absolutePath = [Path stringByExpandingTildeInPath];
NSLog(@"absolutePath:%@",absolutePath);
NSLog(@"Path:%@",[absolutePath stringByAbbreviatingWithTildeInPath]);



//文件擴展名
NSString *Path = @"~/NSData.txt";
NSLog(@"Extension:%@",[Path pathExtension]);




/*******************************************************************************************
NSMutableString
*******************************************************************************************/

/*---------------給字符串分配容量----------------*/
//stringWithCapacity:
NSMutableString *String;
String = [NSMutableString stringWithCapacity:40];


/*---------------在已有字符串後面添加字符----------------*/

//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給出范圍和長度刪除字符------*/
/*
//deleteCharactersInRange:
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];
[String1 deleteCharactersInRange:NSMakeRange(0, 5)];
NSLog(@"String1:%@",String1);



/*--------在已有字符串後面在所指定的位置中插入給出的字符串------*/

//-insertString: atIndex:
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];
[String1 insertString:@"Hi! " atIndex:0];
NSLog(@"String1:%@",String1);



/*--------將已有的空符串換成其它的字符串------*/

//-setString:
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];
[String1 setString:@"Hello Word!"];
NSLog(@"String1:%@",String1);



/*--------按照所給出的范圍,和字符串替換的原有的字符------*/

//-setString:
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];
[String1 replaceCharactersInRange:NSMakeRange(0, 4) withString:@"That"];
NSLog(@"String1:%@",String1);



/*-------------判斷字符串內是否還包含別的字符串(前綴,後綴)-------------*/
//01:檢查字符串是否以另一個字符串開頭- (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:查找字符串某處是否包含其它字符串 - (NSRange) rangeOfString: (NSString *) aString,這一點前面在串中搜索子串用到過;



/*******************************************************************************************
NSArray
*******************************************************************************************/

/*---------------------------創建數組------------------------------*/
//NSArray *array = [[NSArray alloc] initWithObjects:
@"One",@"Two",@"Three",@"Four",nil];

self.dataArray = array;
[array release];

//- (unsigned) Count;數組所包含對象個數;
NSLog(@"self.dataArray cound:%d",[self.dataArray count]);

//- (id) objectAtIndex: (unsigned int) index;獲取指定索引處的對象;
NSLog(@"self.dataArray cound 2:%@",[self.dataArray objectAtIndex:2]);


/*--------------------------從一個數組拷貝數據到另一數組(可變數級)----------------------------*/

//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];


//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];



/*---------------------------切分數組------------------------------*/

//從字符串分割到數組- componentsSeparatedByString:
NSString *string = [[NSString alloc] initWithString:@"One,Two,Three,Four"];
NSLog(@"string:%@",string);
NSArray *array = [string componentsSeparatedByString:@","];
NSLog(@"array:%@",array);
[string release];


//從數組合並元素到字符串- componentsJoinedByString:
NSArray *array = [[NSArray alloc] initWithObjects:@"One",@"Two",@"Three",@"Four",nil];
NSString *string = [array componentsJoinedByString:@","];
NSLog(@"string:%@",string);



/*******************************************************************************************
NSMutableArray
*******************************************************************************************/
/*---------------給數組分配容量----------------*/
//NSArray *array;
array = [NSMutableArray arrayWithCapacity:20];



/*--------------在數組末尾添加對象----------------*/
//- (void) addObject: (id) anObject;
//NSMutableArray *array = [NSMutableArray arrayWithObjects:
@"One",@"Two",@"Three",nil];
[array addObject:@"Four"];
NSLog(@"array:%@",array);



/*--------------刪除數組中指定索引處對象----------------*/
//-(void) removeObjectAtIndex: (unsigned) index;
//NSMutableArray *array = [NSMutableArray arrayWithObjects:
@"One",@"Two",@"Three",nil];
[array removeObjectAtIndex:1];
NSLog(@"array:%@",array);



/*-------------數組枚舉---------------*/
//- (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);
}


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



/*******************************************************************************************
NSDictionary
*******************************************************************************************/

/*------------------------------------創建字典------------------------------------*/
//- (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
*******************************************************************************************/

/*------------------------------------創建可變字典------------------------------------*/
//創建
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);

//刪除指定的字典
[dictionary removeObjectForKey:@"3"];
NSLog(@"dictionary:%@",dictionary);


/*******************************************************************************************
NSValue(對任何對象進行包裝)
*******************************************************************************************/

/*--------------------------------將NSRect放入NSArray中------------------------------------*/
//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);

//從Array中提取
value = [array objectAtIndex:0];
[value getValue:&rect];
NSLog(@"value:%@",value);


/*******************************************************************************************
從目錄搜索擴展名為jpg的文件
*******************************************************************************************/

//NSFileManager *fileManager = [NSFileManager defaultManager];
NSString *home;
home = @"../Users/";

NSDirectoryEnumerator *direnum;
direnum = [fileManager enumeratorAtPath: home];

NSMutableArray *files = [[NSMutableArray alloc] init];

//枚舉
NSString *filename;
while (filename = [direnum nextObject]) {
if([[filename pathExtension] hasSuffix:@"jpg"]){
[files addObject:filename];
}
}

//快速枚舉
//for(NSString *filename in direnum)
//{
// if([[filename pathExtension] isEqualToString:@"jpg"]){
// [files addObject:filename];
// }
//}
NSLog(@"files:%@",files);

//枚舉
NSEnumerator *filenum;
filenum = [files objectEnumerator];
while (filename = [filenum nextObject]) {
NSLog(@"filename:%@",filename);
}

//快速枚舉
//for(id object in files)
//{
// NSLog(@"object:%@",object);
//}







#import

int main (int argc, const char * argv[]) {
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
//創建字符串
NSString *height;
/**類方法:
+(id) stringWithFormat: (NSString *) format,...
通過格式字符串和參數來創建NSString
省略號(。。。):可以接受多個以逗號分割的參數。
這聲明方法時添加加號(+),那麼這個方法為類方法,不需要創建實例就可以調用,通常用於創建心的實例,我們稱用來創建新對象的類方法為工廠方法。
-------------------
objective-c運行時生成一個類的時候,它會創建一個代表該類的類對象。類對象包含了指向超類的指針,類名,和指向類方法列表的指針。類對象還包含一個long型數據,為新創建的類實例對象指定大小(以字節為單位)

類方法可以用來訪問全局數據。

實例方法要用前導減號(-)來開始聲明

*/

height=[NSString stringWithFormat:@"you heigh is %d feet,%d inches",5,11];
NSLog(height);
//length 返回字符串中字符的個數。-(unsigned int) length;
if([height length]>5){
NSLog(@"height length ------");
}

//字符串比較
/**
isEqualToString :可以用來比較接收方和當作參數傳遞來的字符串的內容是否相同,返回yes和no
*/
NSString *thing1=@"hello";
NSString *thing2=[[NSString alloc] initWithString:@"hello"];
if([thing1 isEqualToString:thing2]){
NSLog(@"they are same");
}
/**
==:只判斷指針數值,而不是它們所指向的內容
*/
if(thing1==thing2){
NSLog(@"== same");
}

/*
compare:比較兩個字符串。區分大小寫
compare將接收對象和傳遞來的字符串逐個字符的進行比較,它返回一個NSComparisonResult(枚舉類型)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|添加選項標記
選項:
NSCaseInsensitiveSearch:不區分大小寫字符
NSLiteralSearch:進行完全比較,區分大小寫
NSNumbericSearch:比較字符串的字符個數,而不是字符值
*/
if([thing1 compare:thing2 options:NSCaseInsensitiveSearch|
NSNumericSearch]==NSOrderedSame){
NSLog(@"they match");
}

/**
以某個字符串開始或結尾
-(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 可變字符串
//SString 是不可變的,一旦NSString 被創建了,我們就不能改變它。

//+(id) stringWithCapacity:(unsinged) capacity; capacity:是給NSMutableString的一個建議,字符串的大小並不局限於所提供的大小,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);

//與實例方法一樣,繼承對類方法也同樣適用

//------------------集合--------------
//NSArray ,NSDictionary
/**
NSArray 是一個cocoa類,用來存儲對象的有序列表。
NSArray有兩個限制:1,它只能存儲objective-c的對象,而不能存儲c語言中的基本數據類型如int,float,enum,struct,或者nsarray中的隨機指針。2,不能這nsarray中存儲nil

類方法:
arrayWithObjects:創建一個新的nsarray。發送一個以逗號分割的對象列表,這列表結尾添加nil代表列表結束,(這就是不能這nsarray中存儲nil的原因)

*/
NSArray *array=[NSArray arrayWithObjects:@"aa",@"bb",@"cc",nil];

//-(unsigned) count; 取得包含對象的個數
//-(id) objectAtIndex:(unsigned int) index; 取得索引位置的對象

int i;
for (i=0; i<[array count]; i++) {
NSLog(@"index %d has %@",i,[array objectAtIndex:i]);
}

//------------切分數組
//-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: 合並nsarray中的元素來創建字符串
NSString *joinedStr=[comArr componentsJoinedByString:@"-->"];
NSLog(@"joined---= %@",joinedStr);

//可變數組
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; 刪除指定索引的對象,
//刪除一個對象之後,數組中並沒有留下漏洞,被刪除對象後面的數組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]);
}

//枚舉
//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);
}

//快速枚舉
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字符串)下存儲一個數值(可以是任何類型的對象)。然後你可以用這個關鍵字來查找相應的數值。
NSDictionary 是鍵查詢的優化存儲方式。它可以立即找出要查詢的數據,而不需要遍歷整個數組進行查找。

+(id) dictionaryWithObjectAndKeys:(id) firstObject,....;
該方法接收對象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類來包裝基本數據類型
+(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;
傳遞的參數是你想要包裝的數值的地址,通常,得到的是你想要存儲的變量的地址(在c語言裡適用操作符 & ),你也可以提供一個描述這個數據類型的字符串,通常用來說明struct中實體的類型和大小。你不用自己寫代碼
來生成這個字符串,@encode編譯器指令可以接受數據類型的名稱並為你生成合適的字符串
*/
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 提取數據
/**
-(void) getValue:(void *) value; 要傳遞的是存儲這個數值的變量的地址
*/

/***
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;
}

  1. 上一頁:
  2. 下一頁:
Copyright © 程式師世界 All Rights Reserved