ios的NSMutableString用法

//  
//  main.m  
//  Foundation5-NSMutableString  
//  
//  Created by mj on 13-4-5.  
//  Copyright (c) 2013年 itcast. All rights reserved.  
//  

#import <Foundation/Foundation.h>  

#pragma mark 可变字符串的创建  
void stringCreate() {  
    // 预先分配10个字数的存储空间  
    NSMutableString *str = [[NSMutableString alloc] initWithCapacity:10];  
    // 设置字符串内容  
    [str setString:@"1234"];  

    // 拼接一个字符串  
    [str appendString:@"567"];  
    // 拼接字符串  
    [str appendFormat:@"age is %i and height is %.2f", 27, 1.55f];  

    // 替换字符串  
    NSRange range = [str rangeOfString:@"height"];//查找字符串height的位置  
    [str replaceCharactersInRange:range withString:@"no"];  

    // 插入字符串  
    [str insertString:@"abc" atIndex:2];  

    // 删除字符串  
    range = [str rangeOfString:@"age"];  
    [str deleteCharactersInRange:range];  
    NSLog(@"%@", str);  

    // 释放对象  
    [str release];  
}  

int main(int argc, const char * argv[])  
{  
    @autoreleasepool {  
        stringCreate();  
    }  
    return 0;  
}