Editing Standard streams (section)

===2000s: .NET ===
In [[C Sharp (programming language)|C#]] and other [[.NET Framework|.NET]] languages, the standard streams are referred to by <code>System.Console.In</code> (for stdin), <code>System.Console.Out</code> (for stdout) and <code>System.Console.Error</code> (for stderr).<ref>{{Cite web|url=https://referencesource.microsoft.com/#mscorlib/system/console.cs,34|title= .NET Framework 4.7.1, mscorlib, console.cs |website=Reference Source - Microsoft |access-date=2017-12-10 |url-status=live |archive-url= https://web.archive.org/web/20171210072215/https://referencesource.microsoft.com/#mscorlib/system/console.cs,34 |archive-date= Dec 10, 2017 }}</ref> Basic read and write capabilities for the stdin and stdout streams are also accessible directly through the class <code>System.Console</code> (e.g. <code>System.Console.WriteLine()</code> can be used instead of <code>System.Console.Out.WriteLine()</code>).

<code>System.Console.In</code>, <code>System.Console.Out</code> and <code>System.Console.Error</code> are <code>System.IO.TextReader</code> (stdin) and <code>System.IO.TextWriter</code> (stdout, stderr) objects, which only allow access to the underlying standard streams on a text basis. Full binary access to the standard streams must be performed through the <code>System.IO.Stream</code> objects returned by <code>System.Console.OpenStandardInput()</code>, <code>System.Console.OpenStandardOutput()</code> and <code>System.Console.OpenStandardError()</code> respectively.
<syntaxhighlight lang="c#">
// C# example
public static int Main(string[] args)
{
    try {
        string s = System.Console.In.ReadLine();
        double number = double.Parse(s);
        System.Console.Out.WriteLine("Number is: {0:F3}", number);
        return 0;

    // If Parse() threw an exception
    } catch (ArgumentNullException) { 
        System.Console.Error.WriteLine("No number was entered!");
    } catch (FormatException) {
        System.Console.Error.WriteLine("The specified value is not a valid number!");
    } catch (OverflowException) {
        System.Console.Error.WriteLine("The specified number is too big!");
    }

    return -1;
}
</syntaxhighlight>

<syntaxhighlight lang="vbnet">
' Visual Basic .NET example

Public Function Main() As Integer
    Try
        Dim s As String = System.Console.[In].ReadLine()
        Dim number As Double = Double.Parse(s)
        System.Console.Out.WriteLine("Number is: {0:F3}", number)
        Return 0

    ' If Parse() threw an exception
    Catch ex As System.ArgumentNullException
        System.Console.[Error].WriteLine("No number was entered!")
    Catch ex2 As System.FormatException
        System.Console.[Error].WriteLine("The specified value is not a valid number!")
    Catch ex3 As System.OverflowException
        System.Console.[Error].WriteLine("The specified number is too big!")
    End Try

    Return -1
End Function
</syntaxhighlight>

When applying the <code>System.Diagnostics.Process</code> [[class (computer science)|class]] one can use the instance [[Property (programming)|properties]] <code>StandardInput</code>, <code>StandardOutput</code>, and <code>StandardError</code> of that class to access the standard streams of the process.