#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:];

    // 设置字符串内容

    [str setString:@""];

    // 拼接一个字符串

    [str appendString:@""];

    // 拼接字符串

    [str appendFormat:@"age is %i and height is %.2f", , 1.55f];

    // 替换字符串

    NSRange range = [str rangeOfString:@"height"];

    //NSRange range = NSMakeRange(7, 3);

    [str replaceCharactersInRange:range withString:@"no"];

    // 插入字符串

    [str insertString:@"abc" atIndex:];

    // 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 ;

}