Check if one string is a prefix of another

Question

I have two strings which I\'d like to compare: String and String:. Is there a library function that would return true when passed these two strings

Answer 1

With string::compare, you should be able to write something like:

bool match = (0==s1.compare(0, min(s1.length(), s2.length()), s2,0,min(s1.length(),s2.length())));

Alternatively, in case we don't want to use the length() member function:

bool isPrefix(string const& s1, string const&s2)
{
    const char*p = s1.c_str();
    const char*q = s2.c_str();
    while (*p&&*q)
        if (*p++!=*q++)
            return false;
    return true;
}