/// <summary>
/// Add a command to construct a command pipeline.
/// For example, to construct a command string "get-process | sort-object",
/// <code>
/// PSCommand command = new PSCommand("get-process").AddCommand("sort-object");
/// </code>
/// </summary>
/// <param name="command">
/// A string representing the command.
/// </param>
/// <exception cref="InvalidPowerShellStateException">
/// Powershell instance cannot be changed in its
/// current state.
/// </exception>
/// <returns>
/// A PSCommand instance with <paramref name="cmdlet"/> added.
/// </returns>
/// <remarks>
/// This method is not thread safe.
/// </remarks>
/// <exception cref="ArgumentNullException">
/// cmdlet is null.
/// </exception>
public PSCommand AddCommand(string command)
{
if (command == null)
{
throw PSTraceSource.NewArgumentNullException("cmdlet");
}
if (_owner != null)
{
_owner.AssertChangesAreAccepted();
}
_currentCommand = new Command(command, false);
_commands.Add(_currentCommand);
return(this);
}