C++メモ(二十六)ファイル
2018 ワード
#include
#include
#include
/* streambuf: ios_base:io ios: ios_base , streambuf 。 ostream:ios , istream:ios , iostream: ostream istream, 。 fstream: , ofstream ifstream,ofstream ostream,ifstream istream。 */
int main()
{
using namespace std;
string filename = "E:/a.txt";
/* : ios_base::in, ios_base::out, , ios_base::ate, ios_base::app, ios_base::binary, */
//
ofstream fout;
fout.open(filename,ios_base::app);
if (fout.is_open()) {
fout << "aaaaaaaaaaaaaaaaaa
";
fout << "bbbbbbbbbbbbbbbbbb
";
fout << "cccccccccccccccccc
";
fout.close();
}
//
ifstream fin;
fin.open(filename,ios_base::in);
if (fin.is_open()) {
char ch;
while (fin.get(ch)) {
cout << ch;
}
fin.close();
}
return 0;
}
2回実行した後、結果を出力します.
aaaaaaaaaaaaaaaaaa
bbbbbbbbbbbbbbbbbb
cccccccccccccccccc
aaaaaaaaaaaaaaaaaa
bbbbbbbbbbbbbbbbbb
cccccccccccccccccc