I have a VC++ character array "wchar_t arr[0x30] = { 0x0,0x1,..., 0xC...hexadecimal initialization here ......} ". There is one more C++ character pointer wchar_t * xyz .
An operation something like---- wchar_t ch = arr[xyz[2]] is done. Can someone kindly explain in detail what is happening in this, because arr[] is a char array and we should pass an integer as an index to any array right? But here the index passed to the character array "arr[] " is another character pointer xyz[2]. In the above code suppose a character 'a' is stored at xyz[2] than does it mean we are indexing a C++ character array like this--- arr[xyz[2]] becomes arr['a']. Kindly let me know. How can I achieve this in c SHarp.. Probably if I get to know that what is happening in C++ code above I can myself achieve it in C SHarp. Can anyone kindly let me know what is happening here in this C++ code.
What happens is that the wchar_t
stored at xyz[2]
is promoted to an int
, then used as an index into the arr
array.
It also means that, if xyz[2]
contains L'a'
, the program will exhibit undefined behavior , since arr
only has space for 48
items but L'a'
will be promoted to 97
.
Concerning the second part of your question, C# only supports pointer arithmetic inside unsafe
blocks, so you'll probably want to use arrays instead:
char[] arr = new char[0x30];
char[] xyz = Something();
char ch = arr[xyz[2]];
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