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

You could always loop through and just erase all non alphanumeric characters if you're using string.

#include 

size_t i = 0;
size_t len = str.length();
while(i < len){
    if (!isalnum(str[i]) || str[i] == ' '){
        str.erase(i,1);
        len--;
    }else
        i++;
}

Someone better with the Standard Lib can probably do this without a loop.

If you're using just a char buffer, you can loop through and if a character is not alphanumeric, shift all the characters after it backwards one (to overwrite the offending character):

#include 

size_t buflen = something;
for (size_t i = 0; i < buflen; ++i)
    if (!isalnum(buf[i]) || buf[i] != ' ')
        memcpy(buf[i], buf[i + 1], --buflen - i);