How to convert char array to uintmax_t? [duplicate] - c++

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Convert char array to single int?
How to convert char array to uintmax_t?
char array contains the uintMax_t value but in string format.
Thank you.

You need to use atoi or atol .

Related

how to convert char to wchar_t in C++ [duplicate]

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How to convert string to wstring in C++
(1 answer)
How to convert char* to wchar_t*?
(9 answers)
How to convert UTF-8 std::string to UTF-16 std::wstring?
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Closed 2 months ago.
This post was edited and submitted for review 2 months ago and failed to reopen the post:
Original close reason(s) were not resolved
If I have this below code -
string str;
wstring wstr;
for (char x : str)
{
wstr += x;
}
Is this line wstr += x wrong? Do I need some conversion function to convert char x to wchar_t to be stored in wstr? If yes, which conversion function do I need?
Edit - I have gone through the linked answers, it mentions about converting the array of wchar_t and char -> for that for sure conversion functions are needed but my question specifically asks if a char -> wchar_t would need conversion function

Convert char[] variable to uintptr_t variable C++ [duplicate]

This question already has answers here:
C++ convert hex string to signed integer
(10 answers)
Closed 1 year ago.
I have a variable of type char [] with an address. Example: char addr[11] = "0x01234567";. How do I convert this variable to type uintptr_t?
I want it to be equivalent to uintptr_t add = 0x01234567;.
"0x01234567" is a textual representation of an integer. std::uintptr_t is an integer type. You can use any standard formatted input functions to do the conversion. There are several options, but I recommend starting with a string stream.

convert std::string to unsigned char [duplicate]

This question already has answers here:
How to convert a string of hex values to a string?
(4 answers)
Converting a hex string to a byte array
(22 answers)
Closed 4 years ago.
I have a string like this:
std::string s="840D8E88B0AC";
and an array:
char MAC[6];
I want to produce this:
MAC={0x84,0x0D,0x8E,0x88,0xB0,0xAC};
I try with sscanf() but I can't make it.
sscanf(s.c_str(), "%02X%02X%02X%02X%02X%02X", MAC[0], MAC[1], MAC[2], MAC[3], MAC[4], MAC[5]);
It should be (other errors notwithstanding)
sscanf(s.c_str(), "%02X%02X%02X%02X%02X%02X", &MAC[0], &MAC[1], &MAC[2],
&MAC[3], &MAC[4], &MAC[5]);
sscanf (and variants) require pointers in order to change the variables that are being read into.
Surprised your compiler didn't warn you about that error.

How can I convert a "char" to "std::string"? [duplicate]

This question already has answers here:
How to convert a char array to a string?
(5 answers)
Closed 9 years ago.
I'm trying to find how to convert a char array into a std::string, but I can't find anything to do this.
If it is impossible, could you explain me how can I read an std::string but by scanf() and gets() I can't.
Best regards.
The simplest way of making a string from a character array is using a constructor that takes a pointer and the length, like this:
char charArray[] = {'w', 'x', 'y', 'z'};
std:string s(&charArray[1], 2); // s is "xy"
// ^ ^
// | |
// Pointer to the |
// starting position Length

How to extract a subpart of char* [duplicate]

This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
Modify a char* string in C
I have:
char* htmlstring = "htmldata"
How do I extract:
char* htmlstring1 = "htmldata before </body>tag"
char* htmlstring2 ="htmldata after and including</body> tag"
Can I use strstr? Whats the best approach?
strncpy(destination_string, source + start, count)
It's not really safe, but works. You should wrap it around.