c++ - Qt hex representation of a negative 8bit int? -


However, I am looking for a QT solution.

I'm looking for a way to convert an 8-bit negative int into a hex representation by example it would be better understood. 

  qint8 width = - 100; QDebug () & lt; & Lt; Caststring :: Number (width, 16); // "ffffffffffff9c"   
 Output is greater than 2 bytes.  
 However, when I change it into unsigned, it works fine.  
  quint8 width = - 100; QDebug () & lt; & Lt; Caststring :: Number (width, 16); // "9C"   
 The documentation says:  
 
 typedef quint8  
 supported by Q type for unsigned char This type of 8-bit guarantee is available on all platforms.   
 
 
 Type Type qint8  
 This type of 8-bit guarantee is guaranteed on all platforms supported by Q.   
 Should not be unsigned, not able to deal with negative numbers?   
 
 
 The problem is that  QString :: number   int  or  uint  Type There are no 8-bit integers versions, so these are kept in bigger integers in the whole. It works well with signed integers because the leading zeroes are removed.  
 Although you can use  QDataStream , this code for  operator  provides type:  
  QByteArray buffer; QDataStream Stream (and Buffer, QIODevice :: WriteOnly); Qint8 width = - 100; Stream & lt; & Lt; Width; QDebug () & lt; & Lt; Buffer.toHex (); // Output: "9c"

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