How do I convert a NSString into a std::string?

Question

I have an NSString object and want to convert it into a std::string.

How do I do this in Objective-C++?

Answer 1

As noted on philjordan.eu it could also be that the NSString is nil. In such a case the cast should be done like this:

// NOTE: if foo is nil this will produce an empty C++ string

// instead of dereferencing the NULL pointer from UTF8String.

This would lead you to such a conversion:

NSString *foo = @"Foo";
std::string bar = std::string([foo UTF8String], [foo lengthOfBytesUsingEncoding:NSUTF8StringEncoding]);