c++ 利用stringstream进行类型转换

#include <iostream>
#include <sstream>
#include <string>

using namespace std;

template<typename From, typename To>
bool typeCaste(const From& from, To& to) {
    std::stringstream ss;
    if (!(ss<<from && ss>>to && ss.eof())) {
        return false;
    }
    return true;
}

int main() {
    string a = "hello 123 456";
    stringstream ss;
    ss << a;
    string key;
    int v1, v2;
    ss >> key >> v1 >> v2;
    cout<<key<<endl;
    cout<<v1<<endl;
    cout<<v2<<endl;

    string from = "";
    double to;
    bool flag = typeCaste(from, to);
    cout<<flag<<endl;
    cout<<to<<endl;

    from = "123.456";
    flag = typeCaste(from, to);
    cout<<flag<<endl;
    cout<<to<<endl;

    return 0;
}

结果：

hello
123
456
0
8.33705e-315
1
123.456