C# 0 The Complete Reference

KeyChar

 contains the 

char

 equivalent of the character that was pressed. 

Key

 contains a 

value from the 

ConsoleKey

 enumeration, which is an enumeration of all the keys on the 

keyboard. 

Modifiers

 describes which, if any, of the keyboard modifiers 

ATL

,

CTRL

, or 

SHIFT

were pressed when the keystroke was generated. These modifiers are represented by the 

ConsoleModifiers

 enumeration, which has these values: 

Control

,

Shift

, and 

Alt

. More than 

one modifier value might be present in 

Modifiers

.

The major advantage to 

ReadKey( )

 is that it provides a means of achieving interactive 

keyboard input because it is not line buffered. To see the effect of this, try the following 

program:

// Read keystrokes from the console by using ReadKey().

using System;

class ReadKeys {

  static void Main() {

    ConsoleKeyInfo keypress;

    Console.WriteLine("Enter keystrokes. Enter Q to stop.");

    do {

      keypress = Console.ReadKey(); // read keystrokes

      Console.WriteLine(" Your key is: " + keypress.KeyChar);

      // Check for modifier keys.

      if((ConsoleModifiers.Alt & keypress.Modifiers) != 0)

        Console.WriteLine("Alt key pressed.");

      if((ConsoleModifiers.Control & keypress.Modifiers) != 0)

        Console.WriteLine("Control key pressed.");

      if((ConsoleModifiers.Shift & keypress.Modifiers) != 0)

        Console.WriteLine("Shift key pressed.");

    } while(keypress.KeyChar != 'Q');

  }

}

A sample run is shown here:

Enter keystrokes. Enter Q to stop.

a Your key is: a

b Your key is: b

d Your key is: d

A Your key is: A

Shift key pressed.

B Your key is: B

Shift key pressed.

C Your key is: C

Shift key pressed.

• Your key is: •

Control key pressed.

Q Your key is: Q

Shift key pressed.

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