.NET FrameworkFile Input/Output

Parameters

ParameterDetails
string pathPath of the file to check. (relative or fully qualified)

Remarks

Returns true if the file exists, false otherwise.

VB WriteAllText

Imports System.IO

Dim filename As String = "c:\path\to\file.txt"
File.WriteAllText(filename, "Text to write" & vbCrLf)

VB StreamWriter

Dim filename As String = "c:\path\to\file.txt"
If System.IO.File.Exists(filename) Then
    Dim writer As New System.IO.StreamWriter(filename)
    writer.Write("Text to write" & vbCrLf) 'Add a newline
    writer.close()
End If

C# StreamWriter

using System.Text;
using System.IO;

string filename = "c:\path\to\file.txt";
//'using' structure allows for proper disposal of stream.
using (StreamWriter writer = new StreamWriter(filename"))
{
    writer.WriteLine("Text to Write\n");
}

C# WriteAllText()

using System.IO;
using System.Text;

string filename = "c:\path\to\file.txt";
File.writeAllText(filename, "Text to write\n");

C# File.Exists()

using System;
using System.IO;
                
public class Program
{
    public static void Main()
    {
        string filePath = "somePath";
    
        if(File.Exists(filePath))
        {
            Console.WriteLine("Exists");
        }
        else
        {
            Console.WriteLine("Does not exist");    
        }
    }
}

Can also be used in a ternary operator.

Console.WriteLine(File.Exists(pathToFile) ? "Exists" : "Does not exist");