C++ How to get substring after a character?

问题:

For example, if I have

string x = "dog:cat";

and I want to extract everything after the ":", and return cat. What would be the way to go about doing this?

回答1:

Try this:

x.substr(x.find(":") + 1); 

回答2:

I know it will be super late but I am not able to comment accepted answer. If you are using only a single character in find function use '' instead of "". As Clang-Tidy says The character literal overload is more efficient.

So x.substr(x.find(':') + 1)

回答3:

#include <iostream>
#include <string>

int main(){
  std::string x = "dog:cat";

  //prints cat
  std::cout << x.substr(x.find(":") + 1) << '\n';
}

Here is an implementation wrapped in a function that will work on a delimiter of any length:

#include <iostream>
#include <string>

std::string get_right_of_delim(std::string const& str, std::string const& delim){
  return str.substr(str.find(delim) + delim.size());
}

int main(){

  //prints cat
  std::cout << get_right_of_delim("dog::cat","::") << '\n';

}

回答4:

The accepted answer from rcs can be improved. Don't have rep so I can't comment on the answer.

std::string x = "dog:cat";
std::string substr;
auto npos = x.find(":");

if (npos != std::string::npos)
    substr = x.substr(npos + 1);

if (!substr.empty())
    ; // Found substring;

Not performing proper error checking trips up lots of programmers. The string has the sentinel the OP is interested but throws std::out_of_range if pos > size().

basic_string substr( size_type pos = 0, size_type count = npos ) const;

回答5:

Try this:

  string x="dog:cat";
  int pos = x.find(":");
  string sub = x.substr (pos+1);
  cout << sub;

回答6:

What you can do is get the position of ':' from your string, then retrieve everything after that position using substring.

size_t pos = x.find(":"); // position of ":" in str

string str3 = str.substr (pos);

回答7:

#include <string>
#include <iostream>
std::string process(std::string const& s)
{
    std::string::size_type pos = s.find(':');
    if (pos!= std::string::npos)
    {
        return s.substr(pos+1,s.length());
    }
    else
    {
        return s;
    }
}
int main()
{
    std::string s = process("dog:cat");
    std::cout << s;
}

回答8:

Try this one..

std::stringstream x("dog:cat");
std::string segment;
std::vector<std::string> seglist;

while(std::getline(x, segment, ':'))
{
   seglist.push_back(segment);
}

回答9:

something like this:

string x = "dog:cat";
int i = x.find_first_of(":");
string cat = x.substr(i+1);