How to: Write Text to a File

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ScriptFree

.NET Framework 4

The following example shows how to write text to a text file. It reads all the text files from the user's My Documents folder by using a "*.txt" search pattern, and writes them into a large text file.

Note
Visual Basic users may choose to use the methods and properties provided by the Microsoft.VisualBasic.FileIO.FileSystem class for file I/O.

Example

Visual Basic


Imports System
Imports System.IO
Imports System.Text
Imports System.Collections.Generic

Class Program

    Public Shared Sub Main(ByVal args As String())

        Dim mydocpath As String = _
        Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
        Dim sb As New StringBuilder()

        For Each txtName As String _
            In Directory.EnumerateFiles(mydocpath, "*.txt")
            Using sr As New StreamReader(txtName)
                sb.AppendLine(txtName.ToString())
                sb.AppendLine("= = = = = =")
                sb.Append(sr.ReadToEnd())
                sb.AppendLine()
                sb.AppendLine()

            End Using
        Next

        Using outfile As New StreamWriter(mydocpath & "\AllTxtFiles.txt")
            outfile.Write(sb.ToString())
        End Using
    End Sub
End Class


using System;
using System.IO;
using System.Text;
using System.Collections.Generic;

class Program
{

    static void Main(string[] args)
    {

        string mydocpath = 
        	Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
        StringBuilder sb = new StringBuilder();

        foreach (string txtName in Directory.EnumerateFiles(mydocpath,"*.txt"))
        {
            using (StreamReader sr = new StreamReader(txtName))
            {
                sb.AppendLine(txtName.ToString());
                sb.AppendLine("= = = = = =");
                sb.Append(sr.ReadToEnd());
                sb.AppendLine();
                sb.AppendLine();
            }

        }

        using (StreamWriter outfile = 
        	new StreamWriter(mydocpath + @"\AllTxtFiles.txt"))
        {
            outfile.Write(sb.ToString());
        }
    }
}

Visual C++


using namespace System;
using namespace System::IO;
using namespace System::Text;
using namespace System::Collections::Generic;

ref class Program
{
public:
    static void Main()
    {
        String^ mydocpath =
        	Environment::GetFolderPath(Environment::SpecialFolder::MyDocuments);
        StringBuilder^ sb = gcnew StringBuilder();

        for each (String^ txtName in Directory::EnumerateFiles(mydocpath, "*.txt"))
        {
            StreamReader^ sr = gcnew StreamReader(txtName);
            sb->AppendLine(txtName->ToString());
            sb->AppendLine("= = = = = =");
            sb->Append(sr->ReadToEnd());
            sb->AppendLine();
            sb->AppendLine();
            sr->Close();
        }

        StreamWriter^ outfile = gcnew StreamWriter(mydocpath + "\\AllTxtFiles.txt");
        outfile->Write(sb->ToString());
        outfile->Close();
    }
};

int main()
{
    Program::Main();
}

Community Content

bfbo

A comment about the StringBuilder Class..

In some cases, the StringBuilder Class requires a Type (in this case a String), prior to being declared. For example, if you only wanted to
use the Class Member Main( ) in a Windows Form Class (Form1). See example below:

   //...
   Public:
      String^ sBuilder;
   //...
       //..
       StringBuilder^sb = gcnew StringBuilder(sBuilder);

Go to http://msdn.microsoft.com/en-us/library/system.text.stringbuilder.aspx for more.

Thomas Lee

Writing

Hello
In this example, the Stream Writer is deleting all the text and write the new lines.
How can I do, that it will be written at the end of file?
Please help me!

[tfl - 04 01 12] Hi - and thanks for your post. Community content is not the appropriate place for technical support queries. Instead,
you should visit the Technet Forums at http://forums.microsoft.com/technet, where such posts are welcomed and where you stand a much
better chance of getting your query resolved. Sorry if that's not the answer you wanted to hear.

Thomas Lee

Unable to release memory used by streamwriter!

I am unable to release memory used by streamwriter which finally throws outofmemoryexception. Below is my code

Dim FileTxt as String = "C:\myfile.txt"
Dim swriter As New IO.StreamWriter(FileTxt)
For i = 1 To 1000000
swriter.WriteLine("some text")
Next i
swriter.close()

Please help!!!

[tfl - 04 01 12] Hi - and thanks for your post. Community content is not the appropriate place for technical support queries. Instead,
you should visit the Technet Forums at http://forums.microsoft.com/technet, where such posts are welcomed and where you stand a much
better chance of getting your query resolved. Sorry if that's not the answer you wanted to hear.

How to: Write Text to a File

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