//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
//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);
NSString *path = @"astring.text";
NSString *astring = [[NSString alloc] initWithContentsOfFile:path];
NSLog(@"astring:%@",astring);
[astring release];
NSString *astring = [[NSString alloc] initWithString:@"This is a String!"];
NSLog(@"astring:%@",astring);
NSString *path = @"astring.text";
[astring writeToFile: path atomically: YES];
[astring release];
//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。
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
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];
//-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]);
//stringWithCapacity:
NSMutableString *String;
String = [NSMutableString stringWithCapacity:40];
//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);
*/
//-insertString: atIndex:
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];
[String1 insertString:@"Hi! " atIndex:0];
NSLog(@"String1:%@",String1);
//-setString:
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];
[String1 setString:@"Hello Word!"];
NSLog(@"String1:%@",String1);
//-setString:
NSMutableString *String1 = [[NSMutableString alloc] initWithString:@"This is a NSMutableString"];
[String1 replaceCharactersInRange:NSMakeRange(0, 4) withString:@"That"];
NSLog(@"String1:%@",String1);
//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 *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]);
//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];
//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);
//NSArray *array;
array = [NSMutableArray arrayWithCapacity:20];
//- (void) addObject: (id) anObject;
//NSMutableArray *array = [NSMutableArray arrayWithObjects:
@"One",@"Two",@"Three",nil];
[array addObject:@"Four"];
NSLog(@"array:%@",array);
//-(void) removeObjectAtIndex: (unsigned) index;
//NSMutableArray *array = [NSMutableArray arrayWithObjects:
@"One",@"Two",@"Three",nil];
[array removeObjectAtIndex:1];
NSLog(@"array:%@",array);
//- (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);
}
//- (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];
//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);
//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);
//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;
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
NSString *[email protected]"hello";
NSString *thing2=[[NSString alloc] initWithString:@"hello"];
if([thing1 isEqualToString:thing2]){
NSLog(@"they are same");
}
if(thing1==thing2){
NSLog(@"== same");
}
[thing1 compare:thing2];
if(NSOrderedSame==[thing1 compare:thing2]){
NSLog(@"compare same");
}
//compare:options:
if([thing1 compare:thing2 options:NSCaseInsensitiveSearch|
NSNumericSearch]==NSOrderedSame){
NSLog(@"they match");
}
NSString *[email protected]"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 *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 *[email protected]"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 *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
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
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
//NSNull
[mutableDic setObject:[NSNull null] forKey:@"fax"];
id fax;
fax=[mutableDic objectForKey:@"fax"];
if(fax==[NSNull null]){
NSLog(@"pppppppppppppppppp");
}
[pool drain];
return 0;
}