2012-10-09 123 views
4

新手問題。拆分一個十六進制數

說例如,我有十六進制數0xABCDEF,我將如何將它分爲0xAB,0xCD和0xEF? 是這樣嗎?

unsigned int number = 0xABCDEF 
unsigned int ef = a & 0x000011; 
unsigned int cd = (a>>8) & 0x000011; 
unsigned int ab = (a>>16) & 0x000011; 

感謝

+0

十六進制0x0011是二進制0000000000010001,所以掩碼只會給你兩位而不是全八位。 –

+0

什麼是'a',你的意思是'號碼'? –

回答

12

使用0xff爲你的面具上省去了許多的所有,但8位:

unsigned int number = 0xABCDEF 
unsigned int ef = number & 0xff; 
unsigned int cd = (number>>8) & 0xff; 
unsigned int ab = (number>>16) & 0xff; 
0

用面膜會0xFF,不0x11。除此之外,你是對的。

3
unsigned int number = 0xABCDEF 
unsigned int ef = number & 0xff; 
unsigned int cd = (number >> 8) & 0xff; 
unsigned int ab = (number >> 16) & 0xff; 

取而代之的是按位與(&)操作的,你可能會想這一翻譯efcdabunsigned char類型,這取決於你的代碼的其餘部分,以及如何你與這些變量的工作。在這種情況下在投射到unsigned char

unsigned int number = 0xABCDEF 
unsigned char ef = (unsigned char) number; 
unsigned char cd = (unsigned char) (number >> 8); 
unsigned char ab = (unsigned char) (number >> 16); 
0
void splitByte(unsigned char * split, unsigned int a,int quantBytes) 
{ 
    unsigned char aux; 
    int i; 
    for(i=0;i<quantBytes;i++) 
    { 
     split[i]=a&0x00FF; 
     a=(a>>8); 
    } 
    for(i=0;i<quantBytes-1;i++) 
    { 
     aux = split[i]; 
     split[i] = split[quantBytes-i-1]; 
     split[quantBytes-i-1] = aux; 

    } 
} 

在主: 無符號字符分割[4]; splitByte(split,0xffffffff,4);