How can I convert a character to a integer in Python, and viceversa?
Use chr() and ord(): >>> chr(97) ‘a’ >>> ord(‘a’) 97
char
How to convert a char array back to a string?
No, that solution is absolutely correct and very minimal. Note however, that this is a very unusual situation: Because String is handled specially in Java, even “foo” is actually a String. So the need for splitting a String into individual chars and join them back is not required in normal code. Compare this to C/C++ … Read more
std::string to char*
It won’t automatically convert (thank god). You’ll have to use the method c_str() to get the C string version. std::string str = “string”; const char *cstr = str.c_str(); Note that it returns a const char *; you aren’t allowed to change the C-style string returned by c_str(). If you want to process it you’ll have … Read more
.NET / C# – Convert char[] to string
There’s a constructor for this: char[] chars = {‘a’, ‘ ‘, ‘s’, ‘t’, ‘r’, ‘i’, ‘n’, ‘g’}; string s = new string(chars);
What is an unsigned char?
In C++, there are three distinct character types: char signed char unsigned char If you are using character types for text, use the unqualified char: it is the type of character literals like ‘a’ or ‘0’ (in C++ only, in C their type is int) it is the type that makes up C strings like … Read more
What is the difference between char s[] and char *s?
The difference here is that char *s = “Hello world”; will place “Hello world” in the read-only parts of the memory, and making s a pointer to that makes any writing operation on this memory illegal. While doing: char s[] = “Hello world”; puts the literal string in read-only memory and copies the string to … Read more
How to convert a char to a String?
You can use Character.toString(char). Note that this method simply returns a call to String.valueOf(char), which also works. As others have noted, string concatenation works as a shortcut as well: String s = “” + ‘s’; But this compiles down to: String s = new StringBuilder().append(“”).append(‘s’).toString(); which is less efficient because the StringBuilder is backed by … Read more
How to convert a std::string to const char* or char*
If you just want to pass a std::string to a function that needs const char* you can use std::string str; const char * c = str.c_str(); If you want to get a writable copy, like char *, you can do that with this: std::string str; char * writable = new char[str.size() + 1]; std::copy(str.begin(), str.end(), … Read more
Why is char[] preferred over String for passwords?
Strings are immutable. That means once you’ve created the String, if another process can dump memory, there’s no way (aside from reflection) you can get rid of the data before garbage collection kicks in. With an array, you can explicitly wipe the data after you’re done with it. You can overwrite the array with anything … Read more