您可以使用下面给出的简单技巧将int连接到string，但请注意，这仅适用于integer为个位数时。否则，向该字符串逐位添加整数。

string name = "John";
int age = 5;
char temp = 5 + '0';
name = name + temp;
cout << name << endl;

Output:  John5

有更多的选项可以用来连接整数(或其他数字对象)与字符串。它就是Boost。格式

#include <boost/format.hpp>
#include <string>
int main()
{
    using boost::format;

    int age = 22;
    std::string str_age = str(format("age is %1%") % age);
}

还有Boost的Karma。精神(v2)

#include <boost/spirit/include/karma.hpp>
#include <iterator>
#include <string>
int main()
{
    using namespace boost::spirit;

    int age = 22;
    std::string str_age("age is ");
    std::back_insert_iterator<std::string> sink(str_age);
    karma::generate(sink, int_, age);

    return 0;
}

提振。Spirit Karma声称是整数到字符串转换的最快选择之一。

这是最简单的方法:

string s = name + std::to_string(age);

按字母顺序排列:

std::string name = "John";
int age = 21;
std::string result;

// 1. with Boost
result = name + boost::lexical_cast<std::string>(age);

// 2. with C++11
result = name + std::to_string(age);

// 3. with FastFormat.Format
fastformat::fmt(result, "{0}{1}", name, age);

// 4. with FastFormat.Write
fastformat::write(result, name, age);

// 5. with the {fmt} library
result = fmt::format("{}{}", name, age);

// 6. with IOStreams
std::stringstream sstm;
sstm << name << age;
result = sstm.str();

// 7. with itoa
char numstr[21]; // enough to hold all numbers up to 64-bits
result = name + itoa(age, numstr, 10);

// 8. with sprintf
char numstr[21]; // enough to hold all numbers up to 64-bits
sprintf(numstr, "%d", age);
result = name + numstr;

// 9. with STLSoft's integer_to_string
char numstr[21]; // enough to hold all numbers up to 64-bits
result = name + stlsoft::integer_to_string(numstr, 21, age);

// 10. with STLSoft's winstl::int_to_string()
result = name + winstl::int_to_string(age);

// 11. With Poco NumberFormatter
result = name + Poco::NumberFormatter().format(age);

is safe, but slow; requires Boost (header-only); most/all platforms is safe, requires C++11 (to_string() is already included in #include <string>) is safe, and fast; requires FastFormat, which must be compiled; most/all platforms (ditto) is safe, and fast; requires the {fmt} library, which can either be compiled or used in a header-only mode; most/all platforms safe, slow, and verbose; requires #include <sstream> (from standard C++) is brittle (you must supply a large enough buffer), fast, and verbose; itoa() is a non-standard extension, and not guaranteed to be available for all platforms is brittle (you must supply a large enough buffer), fast, and verbose; requires nothing (is standard C++); all platforms is brittle (you must supply a large enough buffer), probably the fastest-possible conversion, verbose; requires STLSoft (header-only); most/all platforms safe-ish (you don't use more than one int_to_string() call in a single statement), fast; requires STLSoft (header-only); Windows-only is safe, but slow; requires Poco C++ ; most/all platforms

在我看来，最简单的答案是使用sprintf函数:

sprintf(outString,"%s%d",name,age);

#include <string>
#include <sstream>
using namespace std;
string concatenate(std::string const& name, int i)
{
    stringstream s;
    s << name << i;
    return s.str();
}