C# equivalent to Java’s charAt()?
You can index into a string in C# like an array, and you get the character at that index. Example: In Java, you would say In C#, you would say
string
Function stoi not declared
std::stoi was introduced in C++11. Make sure your compiler settings are correct and/or your compiler supports C++11.
variable or field declared void
It for example happens in this case here: Try using std::string instead of just string (and include the <string> header). C++ Standard library classes are within the namespace std::.
java: use StringBuilder to insert at the beginning
Warning: It defeats the purpose of StringBuilder, but it does what you asked. Better technique (although still not ideal): Reverse each string you want to insert. Append each string to a StringBuilder. Reverse the entire StringBuilder when you’re done. This will turn an O(n²) solution into O(n).
Limit String Length
You can use something similar to the below:
Android: How can I Convert String to Date?
From String to Date From Date to String
How to do std::string indexof in C++ that returns index of matching string?
Try the find function. Here is the example from the article I linked:
How to remove first character from C-string?
Or, if the pointer can be modified:
Trim a string in C [duplicate]
There is no standard library function to do this, but it’s not too hard to roll your own. There is an existing question on SO about doing this that was answered with source code.
Lua String replace
Try: See also: http://lua-users.org/wiki/StringLibraryTutorial