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Browse - Programming Tips - How can I efficiently append one byte vector to another?

Date: 2009aug26
Language: C++

Q.  How can I efficiently append one byte vector to another?

A.  

// Here's a fast way to do it: typedef std::vector<BYTE> BYTE_ARRAY; void AppendMemoryToBa(BYTE_ARRAY &ba, const LPVOID in, const size_t size) { size_t before_size = ba.size(); ba.resize(before_size + size); memcpy(ba.begin() + before_size, in, size); } // Append b to a inline void AppendBaToBa(BYTE_ARRAY &a, const BYTE_ARRAY &b) { AppendMemoryToBa(a, (LPVOID)b.begin(), b.size()); }
// Here's the slow way: void SLOW_AppendBaToBa(BYTE_ARRAY &a, const BYTE_ARRAY &b) { for (BYTE_ARRAY::const_iterator it = b.begin(); it != b.end(); it++) { a.push_back(*it); } }

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