// Created by 康大亮。com on 15/10/28.
// Copyright (c) 2015年 康大亮. All rights reserved.
//
#import <Foundation/Foundation.h>
int main(int argc, const char * argv[]) {
#pragma mark- NSString
//创建指定格式的字符串对象
NSString *str1 = [NSString stringWithFormat:@"How old are you"];
//用另一个字符串创建一个新的字符串(适合用于可变字符串)
NSString *str2 = [NSString stringWithString:str1];
NSLog(@"%@",str2);
//读取文本内容为字符串对象
NSString *str = [NSString stringWithContentsOfFile:@"/Users/xalo/Desktop/text.txt" encoding:NSUTF8StringEncoding error:nil];
NSLog(@"%@",str);
//获取字符串长度
NSInteger length = [str length];
NSLog(@"%ld",length);
#pragma mark 根据下标获取字符
for (int i = 0; i < length; i ++) {
NSLog(@"%c",[str1 characterAtIndex:i]);
}
#pragma mark 大、小字符转换
NSString *uperStr = [str1 uppercaseString];
NSLog(@"%@",uperStr);
NSString *lowerStr = [str1 lowercaseString];
NSLog(@"%@",lowerStr);
#pragma mark 首字母大写
NSString *capitalStr = [str1 capitalizedString];
NSLog(@"%@",capitalStr);
#pragma mark 字符串拼接
NSString * str3 = [str1 stringByAppendingString:str2];
NSLog(@"%@",str3);
NSString *str4 = [str1 stringByAppendingFormat:@" %d + %d",2 , 3];
NSLog(@"%@",str4);
#pragma mark 是否包含前缀、后缀
BOOL result = [@"http://www.baidu.com"hasPrefix:@"http"];
NSLog(@"%@",result ? @"YES" : @"NO");
BOOL result1 = [@"http://www.baidu.com"hasSuffix:@"www"];
NSLog(@"%@", result1 ? @"YES" : @"NO");
#pragma mark 搜索字符串范围
NSRange range = [str1 rangeOfString:@"old"];
NSLog(@"%@",NSStringFromRange(range));//NSRange 是结构体类型,起始下标location,长度length,如果存在,length不为0
#pragma mark 字符串截取
NSString *subStr1 = [str1 substringFromIndex:3];//从给定下标开始,包含给定下标
NSString *subStr2 = [str1 substringToIndex:3];//从0开始,返回到给定下标-1(不包含给定下标)
NSRange subRange = NSMakeRange(2, 4);
NSString * subStr3 = [str1 substringWithRange:subRange];//根据指定范围截取
NSLog(@"%@ /%@ /%@",subStr1,subStr2,subStr3);//old are you /How /w ol
#pragma mark 字符串替换
NSString * resultStr = [str1 stringByReplacingOccur rencesOfString:@"old" withString:@"hehe"];
NSLog(@"%@",resultStr);
#pragma mark 字符串对象和基本数据类型的转换
NSString *numStr = @"3.1415";
float num1 = [numStr floatValue];
NSLog(@"%f",num1);
/*@property (readonly) double doubleValue;
@property (readonly) float floatValue;
@property (readonly) int intValue;
@property (readonly) NSInteger integerValue
@property (readonly) long long longLongValue
@property (readonly) BOOL boolValue
*/
#pragma mark NSMutableString
NSMutableString *mutableStr1 = [NSMutableString string ];
//添加字符串
[mutableStr1 setString:@"zhou"];
//拼接字符串
[mutableStr1 appendFormat:@" %d + %d ",1,99];
[mutableStr1 appendString:@"qiang"];
//插入
[mutableStr1 insertString:@"love" atIndex:5];
//替换
[mutableStr1 replaceCharactersInRange:NSMakeRange(0, 3) withString:@"tiantian"];//注意中间的NSMakeRange(把下标为0长度为3的字符替换成XX)
//删除
[mutableStr1 deleteCharactersInRange:NSMakeRange(8, 1)];
NSLog(@"%@",mutableStr1);
#pragma mark- NSNumber
/*
2,字符转int
int intString = [newString intValue];
3,int转字符
NSString *stringInt = [NSString stringWithFormat:@"%d",intString];
4,字符转float
float floatString = [newString floatValue];
5,float转字符
NSString *stringFloat = [NSString stringWithFormat:@"%f",intString];
*/
/*
创建和初始化类方法 初始化实例方法 取值实例方法
numberWithChar: initWithChar: charValue
numberWithShort: initWithShort: shortValue
... ... ...
*/
NSNumber *intObj = [NSNumber numberWithInt:123];//初始化
int intNum = [intObj intValue];//取值