iphone-common-codes-ccteam源代码 CCRadix.m

最新推荐文章于 2012-01-12 09:54:35 发布

最新推荐文章于 2012-01-12 09:54:35 发布 · 74 阅读

本文详细解析了CCRadix.m文件中关于不同基数转换的实现方式，包括十进制到二进制、八进制、十六进制的转换及反向操作。

//
//  CCRadix.m
//  CCFC
//
//  Created by xichen on 11-12-16.
//  Copyright 2011年 __MyCompanyName__. All rights reserved.
//


#include "CCRadix.h"




@implementation CCRadix


+ (NSString *)get2RadixStr:(unsigned)n
{
        return [self getRadixStr:n withRadix:2];
}


+ (NSString *)get8RadixStr:(unsigned)n
{
    return [self getRadixStr:n withRadix:8];
}


+ (NSString *)get10RadixStr:(unsigned)n
{
    return [self getRadixStr:n withRadix:10];
}


+ (NSString *)get16RadixStr:(unsigned)n
{
    NSMutableString *ret = [NSMutableString string];
        while (n)
        {
                int temp = n % 16;
                if(temp >= 10)
                        temp = 'A' + temp - 10;
                
                if(temp < 10)
                        [ret insertString:[NSString stringWithFormat:@"%d", temp] 
                      atIndex:0];
                else
                        [ret insertString:[NSString stringWithFormat:@"%c", temp] 
                                          atIndex:0];
                
                n /= 16;
        }
        return ret;
}


// you should make sure the radix argument is less or equal to 10.
+ (NSString *)getRadixStr:(unsigned)n withRadix:(SMALL_INT)radix
{
    NSMutableString *ret = [NSMutableString string];
        while (n)
        {
                int temp = n % radix;
                [ret insertString:[NSString stringWithFormat:@"%d", temp] 
                                  atIndex:0];
                n /= radix;
        }
        return ret;
}


+ (unsigned)getValueFromStr:(NSString *)str withRadix:(SMALL_INT)radix
{
    int len = [str length];
    if(len == 0)
        return  0;
    
    unsigned sum = 0;
    for(int i = len - 1; i >= 0; --i)
    {
        sum += ([str characterAtIndex:i] - '0') * pow(radix, len - i - 1);
    }
    return sum;
}


// you should make sure the srcStr with srcRadix is valid and not overflow to UINT_MAX.
+ (NSString *)getRadixStr:(NSString *)srcStr 
                 srcRadix:(SMALL_INT)srcRadix 
                destRadix:(SMALL_INT)destRadix
{
    unsigned n = [self getValueFromStr:srcStr withRadix:srcRadix];
    return [self getRadixStr:n withRadix:destRadix];
}


@end

可能有更新:

googlecode链接地址：http://code.google.com/p/iphone-common-codes-ccteam/source/browse/trunk/CCFC/files/CCRadix.m
github地址: https://github.com/cxsjabc/iphone-common-codes-ccteam/tree/master/CCFC/files/CCRadix.m