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Creating a text file containing no control characters?

I need to create a text file in VC++ .NET containing plain numbers with no control characters which can be read with, say, the Notepad (the way text (not binary) files are created in, say, VB.NET). It appears that all examples given in a book such as Deitel’s “Visual C++ .NET. How to Program” create files which contain control characters and encrypt the data. Is that it? Isn’t there a way to create plain and simple text files in VC++ .NET containing no additional characters that can be viewed by common text editors?

nonubik

HANDLE      hFile = CreateFile(m_strFileName, GENERIC_READ, 0, 0, CREATE_NEW, FILE_ATTRIBUTE_HIDDEN, 0);
if (hFile == INVALID_HANDLE_VALUE)
{
      OutputDebugString(_T("\nError creating file"));

}
else
{
TCHAR      szLine[] = _T("Some text here");
      DWORD      dwBytes;
WriteFile(hFile, szLine, sizeof(szLine), &dwBytes, 0);
      CloseHandle(hFile);
{

judico

ASKER

I am having problems implementing above code in managed environment (when trying to use forms). Also, what is the corresponding code for reading the created text file? I would appreciate it very much if you could post a working example using forms in VC++ .NET. Thank you in advance.

judico

ASKER

I found a link that seems to solve the problem:

http://support.microsoft.com/default.aspx?scid=kb;%5BLN%5D;307398&product=vcNET#1

There were several typos to be corrected, otherwise it works fine. Now the problems with OpenFileDialog and SaveFileDialog remain to be solved. To start, how can one change the directory in which the file is written in the code:

StreamWriter* pwriter = new StreamWriter( S"\\KBTest.txt" ); ?

nonubik

StreamWriter* pwriter = new StreamWriter( S"c:\\My_Directory\\KBTest.txt" );

judico

ASKER

This is what I needed:

//This demonstrates how to READ a text file:
      private: System::Void button1_Click(System::Object * sender, System::EventArgs * e)
                   {
// Use try...catch to deal with a 0 byte file or a non-existent file.
listBox1->Items->Clear();

try
{

OpenFileDialog *fileChooser = new OpenFileDialog();
Windows::Forms::DialogResult result = fileChooser->ShowDialog();

// name of file containing data
String *fileName;

// exit event handler if user clicked Cancel
if ( result == DialogResult::Cancel )
return;

// get specified file name
fileName = fileChooser->FileName;

// show error if user specifies invalid data
if ( ( fileName->Equals( S"" ) ) )
MessageBox::Show( S"Invalid File Name", S"Error",
                         MessageBoxButtons::OK, MessageBoxIcon::Error );

else {

       String* textFile = String::Concat( fileName );

}

      StreamReader *reader = new StreamReader(fileName);
      do
      {
      listBox1->Items->Add(reader->ReadLine());
      }
      while(reader->Peek() != -1);
}
catch(FileNotFoundException *ex)
{
      listBox1->Items->Add(ex);
}

catch (System::Exception *e)
{
      listBox1->Items->Add(e);
}

                   }

// This demonstrates how to create and to WRITE to a text file.
private: System::Void button2_Click(System::Object * sender, System::EventArgs * e)
             {

SaveFileDialog *fileChooser = new SaveFileDialog();
Windows::Forms::DialogResult result = fileChooser->ShowDialog();

String *fileName;

fileChooser->CheckFileExists = false;

if ( result == DialogResult::Cancel )
return;

fileName = fileChooser->FileName;

if ( ( fileName->Equals( S"" ) ) )
MessageBox::Show( S"Invalid File Name", S"Error",
                         MessageBoxButtons::OK, MessageBoxIcon::Error );

else {
StreamWriter* pwriter = new StreamWriter( fileName );
pwriter->WriteLine( S"The file was created by using the StreamWriter class." );
pwriter->Close();

listBox1->Items->Clear();
String *filew = new String(S"File written to C:\efi\KBTest.txt");
listBox1->Items->Add(filew);

}

Now, the next step is to find out how to place the two columns of numbers in my text file in two separate arrays which I want to use later in the program.

ASKER CERTIFIED SOLUTION

CetusMOD

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