How to convert a hexadecimal character array into string in C++?

Question

So I have this data packet that I want to send it to my device using TCP/IP protocol. My array is:

unsigned char array1[] = {'0x00', '0x84', '0x00', '0x00', '0x00', '0x06', '0x54', '0x01', '0x00', '0x01', '0x00', '0x03'};

I want this to convert into a string. How do I do it?

Right now I am just manually writing down the decimal equivalent:

unsigned char array1[] = {0,132,0,0,0,6,84,5,0,2,255,0};

and converting it into string:

std::string data ( array1, array1 + sizeof array1 / sizeof array1[0] );

However, I wonder can I use my hex packet just like a string directly?

string x= "00 84 00 00 00 06 54 05 00 02 FF 00";

Also is there a way I can design my message header which is the first 7 bytes that dont change? What changes is the rest of the part?

Note that '0x00' is not really a single "character", it's a multi-byte character literal. Perhaps you mean e.g. unsigned char array1[] = {0x00, 0x84, ... };? Without the quotes? — Some programmer dude
– Some programmer dude, Commented Apr 19, 2017 at 7:20
Why exactly do you want it as std::string? I am not quite sure that this is the "correct" data type... — Simon Kraemer
– Simon Kraemer, Commented Apr 19, 2017 at 7:24
Because my class that I am inheriting, has the function to send this packet over the tcp network. The function only supports string. hence I need to convert my data into string. — Arunava Nag
– Arunava Nag, Commented Apr 19, 2017 at 7:25

const_ref · Accepted Answer · 2017-04-19 07:20:36Z

1

The following code should do what you need.

std::string s { "\x00\x01\x02\x03\x04", 5 };

Use the std::string constructor that also takes the length aka number of bytes.

answered Apr 19, 2017 at 7:20

const_ref

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