重定向后重置cout 我有一个C++程序，在程序中使用： static ofstream s_outF(file.c_str()); if (!s_outF) { cerr << "ERROR : could not open file " << file << endl; exit(EXIT_FAILURE); } cout.rdbuf(s_outF.rdbuf()); 流s_输出的静态（file.c_str（））； 如果（！s_outp） { cerr

在更改

cout

的streambuf之前保存旧的streambuf：

auto oldbuf = cout.rdbuf();  //save old streambuf

cout.rdbuf(s_outF.rdbuf());  //modify streambuf

cout << "Hello File";        //goes to the file!

cout.rdbuf(oldbuf);          //restore old streambuf

cout << "Hello Stdout";      //goes to the stdout!

现在根据范围使用它，如下所示：

cout << "Hello Stdout";      //goes to the stdout!

if ( condition )
{
   restorer modify(cout, s_out);

   cout << "Hello File";     //goes to the file!
}

cout << "Hello Stdout";      //goes to the stdout!

cout
cout << "Hello Stdout";      //goes to the stdout!

if ( condition )
{
   restorer modify(cout, s_out);

   cout << "Hello File";     //goes to the file!
}

cout << "Hello Stdout";      //goes to the stdout!