C# Code Snippet - Execute Shell Commands from .Net

This .Net C# code snippet executes a shell command. To use this function simply provide the file/command to execute, command line parameters (optional), string variable to store output and string variable to store errors occurred during execution.

The code creates a command process and then invokes the command that we want to execute. The result of the command and any errors occurred during execution is stored in a string variables, which can then be used for further reference. This is a great method to execute your DOS commands from .Net.

Code:

/// <summary>
/// Execute a shell command
/// </summary>
/// <param name="_FileToExecute">File/Command to execute</param>
/// <param name="_CommandLine">Command line parameters to pass</param>
/// <param name="_outputMessage">returned string value after executing shell command</param>
/// <param name="_errorMessage">Error messages generated during shell execution</param>
public void ExecuteShellCommand(string _FileToExecute, string _CommandLine, ref string _outputMessage, ref string _errorMessage)
{
    // Set process variable
    // Provides access to local and remote processes and enables you to start and stop local system processes.
 System.Diagnostics.Process _Process = null;
 try
 {
_Process = new System.Diagnostics.Process();
   
   // invokes the cmd process specifying the command to be executed.
        string _CMDProcess = string.Format(System.Globalization.CultureInfo.InvariantCulture, @"{0}\cmd.exe", new object[] { Environment.SystemDirectory });
   
           // pass executing file to cmd (Windows command interpreter) as a arguments
           // /C tells cmd that we want it to execute the command that follows, and then exit.
           string _Arguments = string.Format(System.Globalization.CultureInfo.InvariantCulture, "/C {0}", new object[] { _FileToExecute });
          
           // pass any command line parameters for execution
           if (_CommandLine != null && _CommandLine.Length > 0)
           {
               _Arguments += string.Format(System.Globalization.CultureInfo.InvariantCulture, " {0}", new object[] { _CommandLine, System.Globalization.CultureInfo.InvariantCulture });
           }   
           // Specifies a set of values used when starting a process.
           System.Diagnostics.ProcessStartInfo _ProcessStartInfo = new System.Diagnostics.ProcessStartInfo(_CMDProcess, _Arguments);
           // sets a value indicating not to start the process in a new window.
           _ProcessStartInfo.CreateNoWindow = true;
           // sets a value indicating not to use the operating system shell to start the process.
           _ProcessStartInfo.UseShellExecute = false;
           // sets a value that indicates the output/input/error of an application is written to the Process.
           _ProcessStartInfo.RedirectStandardOutput = true;
           _ProcessStartInfo.RedirectStandardInput = true;
           _ProcessStartInfo.RedirectStandardError = true;
           _Process.StartInfo = _ProcessStartInfo;
   
           // Starts a process resource and associates it with a Process component.
           _Process.Start();   
           // Instructs the Process component to wait indefinitely for the associated process to exit.
        _errorMessage = _Process.StandardError.ReadToEnd();
        _Process.WaitForExit();
 // Instructs the Process component to wait indefinitely for the associated process to exit.
        _outputMessage = _Process.StandardOutput.ReadToEnd();
        _Process.WaitForExit();
       }
    catch (Win32Exception _Win32Exception)
       {
      // Error
        Console.WriteLine("Win32 Exception caught in process: {0}", _Win32Exception.ToString());
       }
    catch (Exception _Exception)
    {
        // Error
           Console.WriteLine("Exception caught in process: {0}", _Exception.ToString());
    }
    finally
       {
           // close process and do cleanup
           _Process.Close();
           _Process.Dispose();
           _Process = null;
       }
   }


Here is a simple example showing how to use above function (ExecuteShellCommand) to execute a simple DOS dir command and show output result in a richtextbox.

Code:

string _Output = null;
   string _Error = null;
   
   ExecuteShellCommand("dir", "c:\\", ref _Output, ref _Error);
   
   richTextBox1.Text = _Output;


This example shows how to use above method to execute DOS del command to delete all the ZIP files in c:\temp folder using .Net.

Code:

/F - Force deleting of read-only files.
/Q - Quiet mode, do not ask if ok to delete on global wildcard.
   string _Output = null;
   string _Error = null;
   
   ExecuteShellCommand("del", "/F /Q c:\\temp\\*.zip", ref _Output, ref _Error);



C# Keywords Used:

Process
Format
ProcessStartInfo
Environment
SystemDirectory
InvariantCulture
Win32Exception
Exception

Code Snippet Information:

Applies To: .Net, C#, CLI, Shell Execute from .Net, DOS, System Processes, Execute DOS Commands from .Net, Redirect Standard Output, Windows command interpreter
Programming Language : C# (C-Sharp)