How to strip all non alphanumeric characters from a string in c++?

Question

I am writing a piece of software, and It require me to handle data I get from a webpage with libcurl. When I get the data, for some reason it has extra line breaks in it. I

Answer 1

Just extending James McNellis's code a little bit more. His function is deleting alnum characters instead of non-alnum ones.

To delete non-alnum characters from a string. (alnum = alphabetical or numeric)

• Declare a function (isalnum returns 0 if passed char is not alnum)

  bool isNotAlnum(char c) {
      return isalnum(c) == 0;
  }
  

• And then write this

  s.erase(remove_if(s.begin(), s.end(), isNotAlnum), s.end());
  

then your string is only with alnum characters.