в 14:21, 25 мая 2010

2010-05-25T14:21:17Z

Admin: 1 версия: Импорт контента...

2010-05-25T10:31:10Z

1 версия: Импорт контента...

Новая страница

==Appending to the End of a File==

<source lang="cpp">#include <fstream>
#include <iostream>
using namespace std;
int main()
{
char buffer[255];
ifstream fin("text.txt");
if (fin)
{
char ch;
while (fin.get(ch))
cout << ch;
}
fin.close();
cout << "in append mode...\n";
ofstream fout("text.txt",ios::app);
if (!fout)
{
cout << "Unable to open for appending.\n";
return(1);
}
cout << "\nEnter text for the file: ";
cin.ignore(1,"\n");
cin.getline(buffer,255);
fout << buffer << "\n";
fout.close();
fin.open("text.txt");
if (!fin)
{
cout << "Unable to open for reading.\n";
return(1);
}
char ch;
while (fin.get(ch))
cout << ch;
fin.close();
return 0;
}</source>

==Open a file as binary file and get its size==

<source lang="cpp">#include <fstream>
#include <iostream>
using namespace std;
int main ()
{
long start,end;
ifstream myfile ("test.txt", ios::in|ios::binary);

start = myfile.tellg();
myfile.seekg (0, ios::end);
end = myfile.tellg();
myfile.close();

cout << "size of " << "test.txt";
cout << " is " << (end-start) << " bytes.\n";
return 0;
}</source>
<pre class=codeResult>size of test.txt is 25 bytes.</pre>

==Open a file for appending and append==

<source lang="cpp">#include <fstream>
#include <iostream>
using namespace std;

int main ()
{
char buffer[256];

fstream myfile;
//open for appending and append
myfile.open("test.txt",ios::app);
myfile << " Hey this is another line \n";
myfile.close();

return 0;
}</source>

==Open a file for input and read in its content==

<source lang="cpp">#include <fstream>
#include <iostream>
using namespace std;

int main ()
{
char buffer[256];

fstream myfile;
// open it for input and read in
myfile.open("test.txt",ios::in);
myfile.getline(buffer,100);
cout << "The file contains " << buffer << "\n";
myfile.close();

return 0;
}</source>
<pre class=codeResult>The file contains This outputting a line.</pre>

==Opening files for read and write.==

<source lang="cpp">#include <fstream>
#include <iostream>
using namespace std;
int main()
{
char buffer[255];
ofstream fout("text.txt");
fout << "test\n";
cout << "Enter text for the file: ";
cin.ignore(1,"\n");
cin.getline(buffer,255);
fout << buffer << "\n";
fout.close();
ifstream fin("text.txt");
char ch;
while (fin.get(ch))
cout << ch;
fin.close();
return 0;
}</source>

==Opening text Files for Read and Write==

<source lang="cpp">#include <fstream>
#include <iostream>
using namespace std;
int main()
{
char buffer[255];
ofstream fout("text.txt");
fout << "this is a test\n";
cout << "Enter text for the file: ";
cin.ignore(1,"\n");
cin.getline(buffer,255);
fout << buffer << "\n";
fout.close();
ifstream fin("text.txt");
cout << "Here"s the contents of the file:\n";
char ch;
while (fin.get(ch))
cout << ch;
fin.close();
return 0;
}</source>

← Предыдущая	Версия 14:21, 25 мая 2010
(нет различий)

C++ Tutorial/File Stream/file open mode - История изменений

в 14:21, 25 мая 2010

Admin: 1 версия: Импорт контента...