I am using Windows Forms C /CLI and have a function that calls a Python script which returns a string representation of bytes. I would like to convert the string to an array of bytes.
For example:
String^ demoString = "09153a"; // example of data returned from Python script
array<Byte>^ bytes;
// This is what I tried but does not give me the output I want
bytes = System::Text::Encoding::UTF8->GetBytes(demoString);
unsigned char zero = bytes[0];
unsigned char one = bytes[1];
unsigned char two = bytes[2];
unsigned char three = bytes[3];
this->richTextBox1->Text = zero "\n";
this->richTextBox1->Text = one "\n";
this->richTextBox1->Text = two "\n";
this->richTextBox1->Text = three "\n";
What this ends up printing to the text box is the decimal representation of the ascii characters:
48
57
49
53
What I am trying to get is an array with the values {0x09, 0x15, 0x3a};
CodePudding user response:
You need a function to parse the hex string by splitting it into pairs, and then converting every pair of hex characters into a byte value.
You can see a complete example below using a console application.
Note: your hex string "09153a"
represents only 3 bytes (so only zero
, one
, two
are relevant).
using namespace System;
array<Byte>^ ParseBytes(String^ str)
{
if (str->Length % 2 != 0)
{
return nullptr;
}
int numBytes = str->Length / 2;
array<Byte>^ bytes = gcnew array<Byte>(numBytes);
for (int i = 0; i < numBytes; i)
{
String^ byteStr = str->Substring(i * 2, 2);
if (!Byte::TryParse(byteStr, Globalization::NumberStyles::HexNumber, nullptr, bytes[i]))
{
return nullptr;
}
}
return bytes;
}
int main(array<System::String ^> ^args)
{
String^ demoString = "09153a"; // example of data returned from Python script
array<Byte>^ bytes = ParseBytes(demoString);
Byte zero = bytes[0];
Byte one = bytes[1];
Byte two = bytes[2];
Console::WriteLine("Hex: 0x" zero.ToString("X2"));
Console::WriteLine("Hex: 0x" one.ToString("X2"));
Console::WriteLine("Hex: 0x" two.ToString("X2"));
return 0;
}
Output:
Hex: 0x09
Hex: 0x15
Hex: 0x3A