//

//  main.m

//  字符串(NSString&NSMutableString)

//

//  Created by 闫合 on 16/5/19.

//  Copyright © 2016年 闫合. All rights reserved.

//

#pragma mark NSString 和 NSMutableString

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[]) {

@autoreleasepool {

//初始化(工厂行为、对象初始化)

//行为

//Foundation框架下有两个字符串的类

//NSString静态类  NSMutableSting动态类

//        NSString *str = @"123";

//类的行为

#pragma mark 通过c字符串来构建一个OC字符串

//可以通过c字符串来构建一个OC字符串

/* char *cstr = "你好!";

NSString *str1 = [NSString stringWithCharacters:cstr length:strlen(cstr)];

NSLog(@"%@",str1);*/

/*  NSString *str = [NSString stringWithFormat:@"%d",123];//把数值转换为字符串“123”

NSLog(@"%@",str);

NSString *str1 = [NSString stringWithString:@"ASD"]; //@"ASD";

NSLog(@"%@",str1);

NSString *str2 = [NSString stringWithUTF8String:"中国"];

NSLog(@"%@",str2);*/

/* NSString *str = [[NSString alloc]initWithFormat:@"%d",123];

NSLog(@"%@",str);

NSString *str1 = [[NSString alloc]initWithString:@"123"];

NSLog(@"%@",str1);*/

#pragma mark 对字符串进行大小写处理

/* //对字符串进行大小写处理

NSString *str = @"abc";

NSLog(@"%@",str);

str = [str uppercaseString];//小写字母转大写

NSLog(@"%@",str);

NSString *str1 = @"aBc";

NSLog(@"%@",str1);

str1 = [str1 lowercaseString];//大写字母转小写

NSLog(@"%@",str1);*/

#pragma mark 判断字符串长度

/* //判断字符串长度

NSString *str = @"123456789";

NSLog(@"%lu",[str length]);//9

NSString *str1 = @"和123";

NSLog(@"%lu",[str1 lengthOfBytesUsingEncoding:NSUTF8StringEncoding]);//在OC里一个汉字占三个字节*/

#pragma mark 判断字符串中是否含有某个字符串

/*

//判断字符串中是否有某个字符串

NSString *str = @"12.3";

NSRange range = [str rangeOfString:@"2."];

//  NSLog(@"length = %lu,location = %lu",range.length,range.location);

if (range.location==NSNotFound)

{

NSLog(@"没有");

}

else

{

NSLog(@"有");

}

*/

#pragma mark 字符串内容比较

/*

//字符串内容比较

NSString *str = @"1234";

if ([str isEqualToString:@"1234"])

{

NSLog(@"是");

}else

{

NSLog(@"不是");

}

*/

#pragma mark 字符串转数值

/*//字符串转数值

NSString *str = @"123";

int s = [str intValue];//转整型

NSLog(@"%d",s);

double d = [str doubleValue];//转double

NSLog(@"%.2f",d);

*/

#pragma mark 判断字符串是否以字符串开头或结尾

//        判断字符串是否以字符串开头或结尾

/*

//是不是以“”开头的

NSString *str = @"12.3";

BOOL b = [str hasPrefix:@"1"];

if (b)

{

NSLog(@"是");

}else

{

NSLog(@"不是");

}

//是不是以“”结尾的

NSString *str1 = @"张三丰";

BOOL b1 = [str1 hasSuffix:@"丰"];

if (b1)

{

NSLog(@"是");

}else

{

NSLog(@"不是");

}

*/

#pragma mark 提取子字符串

//提取子字符串

/*NSString *str = @"我们是中国人??";

NSString *str1 = [str substringFromIndex:6];//从哪个索引位置开始

NSLog(@"str1=%@",str1);

str1 = [str substringToIndex:1];

NSLog(@"str1=%@",str1);//到哪个索引位置结束

NSRange range = {0,2};

str1 = [str substringWithRange:range];//截取某个范围的字符串

NSLog(@"str1=%@",str1);

NSString *str = @"123456";//逆序输出

NSRange range = {0,1};

for (long i=[str length]-1; i>=0; i--)

{

range.location = i;

NSLog(@"%@",[str substringWithRange:range]);

}

*/

#pragma mark 剔除字符串两端的空格stringByTrimmingCharactersInSet

/*

NSString *str = @"123";

NSString *str1 = @" 456";

str1 = [str1 stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];//剔除字符串两端的空格

NSString *str2 = @"7";

NSLog(@"%@%@%@",str,str1,str2);

*/

#pragma mark 写文件到磁盘writeToFile，再读取文件

/*

//        NSString *str = @"123中国";

//      [str writeToFile:@"abc.txt" atomically:YES];//这种写文件的方法已经被弃用了，不推荐使用了

//[str writeToFile:@"abc.txt" atomically:NO encoding:NSUTF8StringEncoding error:nil];

NSString *str;

NSError *error;

str = [NSString stringWithContentsOfFile:@"abc.txt" encoding:NSUTF8StringEncoding error:&error];

NSLog(@"%@",error);

*/

#pragma mark 字符串扩展stringByAppendingString

/*

//字符串扩展stringByAppendingString

NSString *str = @"中国";

//str = [NSString stringWithFormat:@"%@%@",str,@"崛起"];

str = [str stringByAppendingString:@"崛起！"];

NSLog(@"%@",str);

*/

#pragma mark NSMutableSting动态类

NSMutableString *str = [NSMutableString stringWithCapacity:100];//预留100个字符的空间

NSLog(@"%@",str);//此时是空串

//        [str appendString:@"123"];//直接添加字符串"123"

[str appendFormat:@"%d",123];//格式化的添加"123"

NSRange r = {0,2};

[str replaceCharactersInRange:r withString:@""];

NSLog(@"%@",str);

return 0;

}

}