How do I detect "_" in a C++ string?

Question

Hello, I want to know the positions of the "_" in a string:

string str("BLA_BLABLA_BLA.txt");

Something like:

string::iterator it;
for ( it=str.begin() ; it < str.end(); it++ ){
 if (*it == "_")         //this goes wrong: pointer and integer comparison
 {
  pos(1) = it;
 }
 cout << *it << endl;
}

Thanks, André

Answer 1

string::find is your friend. http://www.cplusplus.com/reference/string/string/find/

someString.find('_');

Answer 2

You can make use of the find function as:

string str = "BLA_BLABLA_BLA.txt";
size_t pos = -1;

while( (pos=str.find("_",pos+1)) != string::npos) {
        cout<<"Found at position "<<pos<<endl;
}

Output:

Found at position 3
Found at position 10

Answer 3

Why dont you use the find method : http://www.cplusplus.com/reference/string/string/find/

Answer 4

std::find(str.begin(), str.end(), '_');
                               // ^Single quote!