NSString、NSMutableString基本用法
NSString其实是一个对象类型。NSString是NSObject(Cocoa Foundation的基础对象)的子类
一、NSString的创建
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);
7、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];
8、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];
二、字符串的比较
1、用C比较:strcmp函数
char string1[] = "string!";
char string2[] = "string!";
if(strcmp(string1, string2) = = 0)
{
NSLog(@"1");
}
2、isEqualToString方法
NSString *astring01 = @"This is a String!";
NSString *astring02 = @"This is a String!";
BOOL result = [astring01 isEqualToString:astring02];
NSLog(@"result:%d",result);
3、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)
不考虑大小写比较字符串
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);
P.S : 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。
三、改写字符串
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
四、搜索字符串
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];
五、字符串的截取
1.-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);
2.-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);
3.-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);
4.截取NSString最后一位符号后的东西
方法1.
NSString *str = @"/Users/yangiori/Library/Application Support/iPhone Simulator/5.1/Applicati*****/8724956B-407E-4ACD-BBA6-95C7D033C33D/Documents/content/chapters/8";
NSString *temp1 = [[str componentsSeparatedByString:@"/"] lastObject];
NSLog(@"%@",temp1);
结果:8
方法2.
NSString *str = @"/Users/yangiori/Library/Application Support/iPhone Simulator/5.1/Applicati*****/8724956B-407E-4ACD-BBA6-95C7D033C33D/Documents/content/chapters/8";
NSString *temp2 = [str substringFromIndex:[str length]-1];
NSLog(@"%@",temp2);
结果:8
5.从指定位置截取字符串
NSString * str =[NSString stringWithFormat:@"********************Documents/image%i.jpg",2];
NSRange range = [str rangeOfString:@"Documents"];
NSString * result = [str substringFromIndex:range.location];
NSLog(@"%@",result);
六、其他操作
1.扩展路径
NSString *Path = @"~/NSData.txt";
NSString *absolutePath = [Path stringByExpandingTildeInPath];
NSLog(@"absolutePath:%@",absolutePath);
NSLog(@"Path:%@",[absolutePath stringByAbbreviatingWithTildeInPath]);
2.文件扩展名
NSString *Path = @"~/NSData.txt";
NSLog(@"Extension:%@",[Path pathExtension]);
NSMutableString
基本用法
1.给字符串分配容量
stringWithCapacity:
NSMutableString *String;
String = [NSMutableString stringWithCapacity:40];
2.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);
3.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);
4.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);
5.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);
6.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);
7.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;
NSString、NSMutableString基本用法的更多相关文章
- NSString&NSMutableString常用操作梳理(转)
作者:弦苦 授权本站转载. 上一篇梳理了NSArray&NSMutableArray常用操作,这次来梳理一下Objective-C中每天都要用到的字符串处理类——NSString. Objec ...
- 关于NSString,NSMutableString,NSArray,NSMutableArray,NSDictionary,NSMutableDictionary
NSString,NSMutableString,NSArray,NSMutableArray,NSDictionary,NSMutableDictionary 在 OC 中我们天天都要用,而我们要怎 ...
- NSString&NSMutableString常用操作梳理
http://www.cocoachina.com/ios/20150724/12722.html 上一篇梳理了NSArray&NSMutableArray常用操作,这次来梳理一下Object ...
- [转] NSString / NSMutableString 字符串处理,常用代码
原文 : http://justcoding.iteye.com/blog/1405951 Objective-C 中核心处理字符串的类是 NSString 与 NSMutableString , ...
- 【转】 NSString / NSMutableString 字符串处理,常用代码 (实例)
Objective-C 中核心处理字符串的类是 NSString 与 NSMutableString ,这两个类最大的区别就是NSString 创建赋值以后该字符串的内容与长度不能在动态的更改,除非重 ...
- NSString / NSMutableString 字符串处理,常用代码 (实例)
http://blog.csdn.net/likendsl/article/details/7417878 Objective-C 中核心处理字符串的类是 NSString 与 NSMutableSt ...
- iOS NSString的常用用法
//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 *astrin ...
- NSString NSMutableString copy mutableCopy retain weak strong整合
copy retain assign的差别在于对象属性的set方法 NSString 与 NSMutableString NSString是不可变字符串对象,这句话的意思,结合代码: #import ...
- NSString NSMutableString
// NSString //代开API文档 //Xcode -> help - Documentation and API Reference ...
随机推荐
- 39.递归颠倒栈[ReverseStack]
[题目] 用递归颠倒一个栈.例如输入栈{1, 2, 3, 4, 5},1在栈顶.颠倒之后的栈为{5, 4, 3, 2, 1},5处在栈顶. [分析] 乍一看到这道题目,第一反应是把栈里的所有元素逐一p ...
- iOS 和Android中的正则表达式简单使用
ios 中需要使用NSRegularExpression类,NSTextCheckingResult类. 下面给出最基本的实现代码 NSRegularExpression *regex = [NSRe ...
- glGetFloatv (GL_MODELVIEW_MATRIX, mat)
这个函数的作用是取出GL_MODELVIEW_MATRIX,然后存储在mat这个矩阵中,用于逆变换等.
- JUC回顾之-Semaphore底层实现和原理
1.控制并发线程数的Semaphore Semaphore(信号量)是用来控制同时访问特定资源的线程数量,它通过协调各个线程,保证合理的使用公共资源. 线程可以通过acquire()方法来获取信号量的 ...
- LeetCode之Min Stack 实现最小栈
LeetCode相关的网上资源比较多,看到题目一定要自己做一遍,然后去学习参考其他的解法. 链接: https://oj.leetcode.com/problems/min-stack/ 题目描述: ...
- 为什么在SQL Server2008在视图中修改表结构无效
解决办法: 在SQL server 2008 中,打开菜单-->工具
- 【HTML5】拖放(Drag 和 drop)
效果图: <!DOCTYPE HTML> <html> <head> <style type="text/css"> #div1 { ...
- 开始写github
公司即将开发手机钱庄网,于是最近在写一些手机上常用的js组件做前期准备. 之所以没有沿用pc的那些插件,原因是: 之前的插件大多数是使用jquery写的 移动端的性能要求更严格 以前写的插件从现在看看 ...
- Scala中的Implicit(隐式转换,隐式参数,隐式类)
文章来自:http://www.cnblogs.com/hark0623/p/4196452.html 转发请注明 代码如下: /** * 隐式转换 隐式参数 隐式类 */ //隐式转换 class ...
- 在CentOS下利用Eclipse调试FFmpeg
所需软件 64位软件打包下载链接:http://pan.baidu.com/s/1i3B08Up 密码:o50u https://yunpan.cn/cBKDSbrGDgBvz 访问密码 1f55 ...