How to convert string to hex in c++ is hardly easy to deal with if you are not an expert in C++ programming language. This article would give you a helping hand with every task you want to perform to convert C++ strings to hex. Skip the upcoming content unless you want to figure out the most detailed guidance on this issue!

1. What is a string in C++?

In case you are a newbie in programming, here would explain in detail the full definition of a C++ string before guiding you over how to convert string to hex in c++. Simply saying, a string in C++ is a character sequence arranged in order. When it comes to a deep explanation, the string would be clarified in accordance with 3 dimensions.

Firstly, you can understand the string in C++ as a simple array without special properties as another one.

An example of a simply ordered character string array

Secondly, a C-string is also known as a null-terminated string which contains a character array ended by “\0” (null character). You can create and handle this type of string by utilizing the library of <string>. On the other hand, do not misunderstand that a null character is the last one in the C++ string array.

Finally, a string in C++ is seen as an object belonging to the library of C++ standards. It represents the data type of class, applied for manipulating character sequences conveniently. You can access this string class of the C++ standard library through the std namespace.

An example of the std namespace

The programmer can take a lot of advantages and significantly utilize functionality for C++ strings. Though in fact, you can perform all the tasks utilizing C-strings, it is suggested that you would experience more convenience and efficiency when using strings in C++ only.

2. How to convert string to hex in c++? 

In computer language, hexadecimal represents the numbers that have a base of 16 and can be performed in 16-bit. There contain the integer numbers from 0-15 in hexadecimal. However, from 10 onwards, you will not count as 10, 11, 12, 13, 14, 15 but A, B, C, D, E, and F. That being said, the values 0-9 are presented by the numbers 0-9, and the values 10-15 are presented by the letter A-F.

Due to hexadecimal being widely used by programmers, how to convert string to hex in c++ is also a top concern. Here would provide you with 2 main methods for converting strings in C++ to hex including:

• Convert a string in C++ by applying std::cout and std::hex
• Convert a string in C++ by applying std::stringstream and std::hex

2.1 By applying std::cout and std::hex

Programmers commonly use the hexadecimal notation for the purposes of reading files binary and representing various files of programs, coded format, or text only. Therefore, when in need, programmers will need to create file content by hex data and then output it.

Below would demonstrate an example, in which the output in the console contains the string objects stored as hexadecimal data. Notable, the manipulator of std::hex I/P provided by C++ can adjust the number base of stream data.

You should decompose the string object under single characters. Then, they can separately adjust with std::hex to their corresponding hexadecimal representation. Also, a range-based loop is conducted to repeat the string characters and navigate the adjusted data into the stream of cout.

#include <iostream>
#include <string>
#include <sstream>
#include <iterator>

using std::cout; using std::endl;
using std::string; using std::hex;
using std::stringstream;

int main(){

    string s1 = "This will be converted to hexadecimal";
    string s2;
    cout << "string: " << s1 << endl;
    cout << "hexval: ";
    for (const auto &item : s1) {
        cout << hex << int(item);
    }

    cout << endl;
    return EXIT_SUCCESS;
}

Output:

string: This will be converted to hexadecimal

hexval: 546869732077696c6c20626520636f6e76657274656420746f2068657861646563696d616c

2.2 By applying std::stringstream and std::hex

Though the above method can be used in converting strings in C++ into hex, it remains the limitation of lacking storing feature for the hexadecimal notation within the object.

To solve that, creating an object of stringstream where the iteration would be used for inserting the hex values in string characters is the most recommended solution. When the data can be included in stringstream, it can create an advanced string object to store the adjusted character data.

Keep in mind that you can directly output the data from stringstream object. However, this below example would utilize the string of “cout <<” which is more simple, able to write hexadecimal values into files directly and take advantage of filesystem functions in that standard library.

#include <iostream>
#include <string>
#include <sstream>
#include <iterator>

using std::cout; using std::endl;
using std::string; using std::hex;
using std::stringstream;

int main(){
    string s1 = "This will be converted to hexadecimal";
    string s2;
    stringstream ss;
    cout << "string: " << s1 << endl;
    for (const auto &item : s1) {
        ss << hex << int(item);
    }

    s2 = ss.str();
    cout << "hexval: " << s2 << endl;
    return EXIT_SUCCESS;
}

Output:

string: This will be converted to hexadecimal

hexval: 546869732077696c6c20626520636f6e76657274656420746f2068657861646563696d616cNow you

Final Words

Have acquired 2 methods to convert string to hex in c++. Also, the usability and limitation of each one are also clarified. Hope that those tutorials above would be helpful for you in dealing with troubles in C++ programming. Do not hesitate to explore other posts on the website for more IT knowledge!