//将“⽂文艺⻘青年”改成“213⻘青年”。
NSString *str = @"文艺青年";
NSString *str1 = [str stringByReplacingOccurrencesOfString:@"文艺" withString:@"213"];
NSLog(@"%@",str1);
//将 整数123 转换为字符串“123”。
NSString *s = [NSString stringWithFormat:@"%d",123];
NSLog(@"%@",s);
//将 “i love you”单词⾸首字⺟母变⼤大写 “I love You”
NSString *str2 = @"i love you";
NSLog(@"%@",[str2 capitalizedString]);
//截取字符串“20|http://www.baidu.com”中 “|” 前⾯面和后⾯面的字符串, 并输出。提⽰示:-componentsSeparatedByString:
NSString *st = @"20|http://www.baidu.com";
NSArray *arr = [st componentsSeparatedByString:@"|"];
NSLog(@"第一部分：%@",arr[0]);
NSLog(@"第二部分：%@",arr[1]);
/*******************************************************************************************
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);
// NSString *astring = [[NSString alloc] init];
NSLog(@"0x%.8x", astring);
astring=@"This is a String!";
NSLog(@"0x%.8x", astring);
[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);
//}
摘自:http://hi.baidu.com/jis2007/blog/item/62b47dc2e7cab63be4dd3bff.html/cmtid/58a09f34cee304b9d1a2d331
//NSString-不变的字符串。一个文本字符串时创建并随后无法改变。NSString实现代表一个Unicode字符数组,换句话说,一个文本字符串。
//初始化方法
//1,1 创建 （格式初始化）
NSString *str1 = [[NSString alloc] initWithFormat:@"我是 %@ 年龄 %d",@"通",18];
//NSLog(@"%@",str1);
//1,2 创建,（便利构造器）
NSString *str2 = [NSString stringWithFormat:@"我是 %@ 年龄 %d",@"通",19];
//NSLog(@"%@",str2);
//1,3 简便创建(字面量)
NSString *s3 = @"abcd.mp3";
// NSLog(@"%@",s3);
//1,4 已有字符串创建
NSString *s4 = [NSString stringWithString:s3];
//NSLog(@"%@",s4);
//2，长度
NSLog(@"s3长度：%lu",s3.length);
//3,后缀
if ([s3 hasSuffix:@"mp3"]) {
NSLog(@"有 mp3 后缀");
}
//4,1 截取
NSString *s5 = [@"abcde" substringFromIndex:3];
//NSLog(@"截取到结尾：%@",s5);
//4,2 截取
NSString *s6 = [@"abcde" substringToIndex:3];
//NSLog(@"从头截取：%@",s6);
//4,3 区域截取Range
NSString *s7 = [@"abcde" substringWithRange:NSMakeRange(1, 3)];
//NSLog(@"区域截取：%@",s7);
//4,4 获取位置
NSRange r = [@"abcdefg" rangeOfString:@"bcd"];
NSLog(@"区域：%@", NSStringFromRange(r) );
//5, 测试两个字符串是否相等
if ([@"ss" isEqualToString:@"ss"]) {
NSLog(@"相同");
}else{
NSLog(@"不相同");
}
//6, 追加
NSString *ss3 = [s3 stringByAppendingString:@"dddd"];
NSLog(@"追加：%@",ss3);
//7, 替换
NSString * ss4 = [s3 stringByReplacingOccurrencesOfString:@"abc" withString:@"***"];
NSLog(@"替换：%@",ss4);
//8, 比较
NSLog(@"比较：%d",(int)[@"aa" compare:@"aa"]);
//9,字符串转数值类型
NSInteger in1 = [@"123" intValue];
CGFloat in2 = [@"1.2" floatValue];
NSLog(@"替换：%f",in2);
//10, 大小写转换
NSLog(@"%@",[@"ssd" uppercaseString]);
NSLog(@"%@",[@"sGYH" lowercaseString]);
NSLog(@"%@",[@"ssd" capitalizedString]);//首字母大写
//1,可变字符串
NSMutableString *ms=[NSMutableString stringWithFormat:@"dkfj"];
//插入
[ms insertString:@"ni" atIndex:0];
//追加
[ms appendString:@"dd"];
//删除
[ms deleteCharactersInRange:NSMakeRange(0,3)];
//设置
[ms setString:@"vv"];
//
NSLog(@"%@",ms);