字符串爲十六進制分裂

Question

我有一個的QString：

QString str = "1000140035"; 

我想從上面這樣的字符串中提取每個字節： -

Unsigned char a = 0x10 
Unsigned char b = 0x00 
Unsigned char c = 0x14 
Unsigned char d = 0x00 
Unsigned char e = 0x35 

請建議如何做到這一點？嘗試但失敗了很多次。

Answer 1

QByteArray::fromHex + QString::toLatin1()

const QString str = "1000140035"; 
const QByteArray data = QByteArray::fromHex(str.toLatin1()); 
unsigned char a = data[0]; 
unsigned char b = data[1]; 
unsigned char c = data[2]; 
unsigned char d = data[3]; 
unsigned char e = data[4]; 

Answer 2

也許這是你在找什麼？該代碼將解析任意長度的十六進制字符串並返回一個2位十六進制數字及其數量的數組。它爲結果分配內存，所以你有責任在之後釋放它。提取的數字的數量通過第三個參數返回。

#include <QString> 
#include <cmath> 

unsigned HexToNum(char c) 
{ 
    if(c >= '0' && c <= '9') 
     return c - '0'; 

    if(c >= 'A' && c <= 'F') 
     return 15 + c - 'A'; 

    if(c >= 'a' && c <= 'f') 
     return 15 + c - 'a'; 

    //Non hex char passed, return 0 
    return 0; 
} 

void ExtractBytes(const QString& hexString, unsigned char*& result, int& resultNumbersCount) 
{ 
    resultNumbersCount = static_cast<int>(ceil(hexString.length()/2)); 
    result = new unsigned char[resultNumbersCount]; 

    int i, j = -1; 
    for(i = 0; i < resultNumbersCount; ++i) 
     result[i] = 0; 

    for(i = 0; i < hexString.length(); ++i) 
    { 
     if(i % 2 == 0) 
      ++j; 

     result[j] = result[j] * 16 + HexToNum(hexString.at(i).toLatin1()); 
    } 
} 

Answer 3

您可以使用QString::toInt和基礎設置爲16至十六進制字符串轉換爲int（或QString::toUInt）。

QString str = "1000140035"; 
while(!str.isEmpty()) 
{ 
    unsigned char byte = str.left(2).toInt(0, 16); 
    // do something with byte, store it somewhere or whatever... 
    str.remove(0, 2); 
}