Process::StandardInput Property


Gets a stream used to write the input of the application.

Namespace:   System.Diagnostics
Assembly:  System (in System.dll)

property StreamWriter^ StandardInput {
	StreamWriter^ get();

Property Value

Type: System.IO::StreamWriter^

A StreamWriter that can be used to write the standard input stream of the application.

Exception Condition

The StandardInput stream has not been defined because ProcessStartInfo::RedirectStandardInput is set to false.

A Process can read input text from its standard input stream, typically the keyboard. By redirecting the StandardInput stream, you can programmatically specify the input. For example, instead of using keyboard input, you can provide text from the contents of a designated file or output from another application.


To use StandardInput, you must set ProcessStartInfo::UseShellExecute to false, and you must set ProcessStartInfo::RedirectStandardInput to true. Otherwise, writing to the StandardInput stream throws an exception.

The following example illustrates how to redirect the StandardInput stream of a process. The example starts the sort command with redirected input. It then prompts the user for text, and passes that to the sort process by means of the redirected StandardInput stream. The sort results are displayed to the user on the console.

#using <System.dll>

using namespace System;
using namespace System::IO;
using namespace System::Diagnostics;
using namespace System::ComponentModel;
int main()
   Console::WriteLine(  "Ready to sort one or more text lines..." );

   // Start the Sort.exe process with redirected input.
   // Use the sort command to sort the input text.
   Process^ myProcess = gcnew Process;
   if ( myProcess )
      myProcess->StartInfo->FileName =  "Sort.exe";
      myProcess->StartInfo->UseShellExecute = false;
      myProcess->StartInfo->RedirectStandardInput = true;
      StreamWriter^ myStreamWriter = myProcess->StandardInput;
      if ( myStreamWriter )

         // Prompt the user for input text lines to sort. 
         // Write each line to the StandardInput stream of
         // the sort command.
         String^ inputText;
         int numLines = 0;
            Console::WriteLine(  "Enter a line of text (or press the Enter key to stop):" );
            inputText = Console::ReadLine();
            if ( inputText && inputText->Length > 0 )
               myStreamWriter->WriteLine( inputText );
         while ( inputText && inputText->Length != 0 );

         // Write a report header to the console.
         if ( numLines > 0 )
            Console::WriteLine(  " {0} sorted text line(s) ", numLines.ToString() );
            Console::WriteLine(  "------------------------" );
            Console::WriteLine(  " No input was sorted" );

         // End the input stream to the sort command.
         // When the stream closes, the sort command
         // writes the sorted text lines to the 
         // console.

      // Wait for the sort process to write the sorted text lines.


for full trust for the immediate caller. This member cannot be used by partially trusted code.

.NET Framework
Available since 1.1
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