ConsoleKeyInfo.GetHashCode Method

Definition

Namespace:

System

Assembly:

System.Console.dll

Source:

ConsoleKeyInfo.cs

Returns the hash code for the current ConsoleKeyInfo object.

public:
 override int GetHashCode();

public override int GetHashCode ();

override this.GetHashCode : unit -> int

Public Overrides Function GetHashCode () As Integer

Returns

Int32

A 32-bit signed integer hash code.

Examples

The following example demonstrates the GetHashCode method.

using namespace System;
using namespace System::Text;

String^ KeyCombination(ConsoleKeyInfo sourceCki);

void main()
{
   String^ k1 = "\nEnter a key ......... ";
   String^ key1 = "";
   String^ hashCodeFmt = "The hash code for the {0} key is {1}.";
   String^ prompt = "Press the escape key (ESC) to quit, " + 
                    "or any other key to continue.";
   ConsoleKeyInfo cki1;
   int hashCode = 0;

   // The Console.TreatControlCAsInput property prevents this example from
   // ending if you press CTL+C, however all other operating system keys and 
   // shortcuts, such as ALT+TAB or the Windows Logo key, are still in effect. 
   //
   Console::TreatControlCAsInput = true;

   // Request that the user enter two key presses. A key press and any 
   // combination shift, CTRL, and ALT modifier keys is permitted.
   do 
   {
      Console::Write(k1);
      cki1 = Console::ReadKey(false);
      Console::WriteLine();

      key1 = KeyCombination(cki1);
      hashCode = cki1.GetHashCode();
      Console::WriteLine(hashCodeFmt, key1, hashCode);

      Console::WriteLine(prompt);
      cki1 = Console::ReadKey(true);
   } while (cki1.Key != ConsoleKey::Escape);
   // Note: This example requires the Escape (Esc) key.
}

// The KeyCombination() method creates a string that specifies what 
// key and what combination of shift, CTRL, and ALT modifier keys 
// were pressed simultaneously.

static String^ KeyCombination(ConsoleKeyInfo sourceCki)
{
   StringBuilder^ sb = gcnew StringBuilder();
   sb->Length = 0;
   String^ keyCombo;
   if (sourceCki.Modifiers != (ConsoleModifiers) 0)
      {
      if ((sourceCki.Modifiers & ConsoleModifiers::Alt) != (ConsoleModifiers) 0)
         sb->Append("ALT+");
      if ((sourceCki.Modifiers & ConsoleModifiers::Shift) != (ConsoleModifiers) 0)
         sb->Append("SHIFT+");
      if ((sourceCki.Modifiers & ConsoleModifiers::Control) != (ConsoleModifiers) 0)
         sb->Append("CTL+");
      }
   sb->Append(sourceCki.Key.ToString());
   keyCombo = sb->ToString();
   return keyCombo;
}


/*
This example produces results similar to the following output:

Enter a key ......... a
The hash code for the A key is 97.
Press the escape key (ESC) to quit, or any other key to continue.

Enter a key ......... S
The hash code for the SHIFT+S key is 83.
Press the escape key (ESC) to quit, or any other key to continue.

Enter a key .........
The hash code for the ALT+SHIFT+CTL+J key is 7.
Press the escape key (ESC) to quit, or any other key to continue.

*/

// This example demonstrates the ConsoleKeyInfo.GetHashCode() method.

using System;
using System.Text;

class Sample
{
    public static void Main()
    {
    string k1 = "\nEnter a key ......... ";
    string key1 = "";
    string hashCodeFmt = "The hash code for the {0} key is {1}.";
    string prompt = "Press the escape key (ESC) to quit, " +
                    "or any other key to continue.";
    ConsoleKeyInfo cki1;
    int hashCode = 0;

//
// The Console.TreatControlCAsInput property prevents this example from
// ending if you press CTL+C, however all other operating system keys and
// shortcuts, such as ALT+TAB or the Windows Logo key, are still in effect.
//
    Console.TreatControlCAsInput = true;

// Request that the user enter two key presses. A key press and any
// combination shift, CTRL, and ALT modifier keys is permitted.
    do
    {
        Console.Write(k1);
        cki1 = Console.ReadKey(false);
        Console.WriteLine();
//
        key1 = KeyCombination(cki1);
        hashCode = cki1.GetHashCode();
        Console.WriteLine(hashCodeFmt, key1, hashCode);
//
        Console.WriteLine(prompt);
        cki1 = Console.ReadKey(true);
    } while (cki1.Key != ConsoleKey.Escape);
// Note: This example requires the Escape (Esc) key.
    }

// The KeyCombination() method creates a string that specifies what
// key and what combination of shift, CTRL, and ALT modifier keys
// were pressed simultaneously.

    protected static string KeyCombination(ConsoleKeyInfo sourceCki)
    {
    StringBuilder sb = new StringBuilder();
    sb.Length = 0;
    string keyCombo;
    if (sourceCki.Modifiers != 0)
        {
        if ((sourceCki.Modifiers & ConsoleModifiers.Alt) != 0)
            sb.Append("ALT+");
        if ((sourceCki.Modifiers & ConsoleModifiers.Shift) != 0)
            sb.Append("SHIFT+");
        if ((sourceCki.Modifiers & ConsoleModifiers.Control) != 0)
            sb.Append("CTL+");
        }
    sb.Append(sourceCki.Key.ToString());
    keyCombo = sb.ToString();
    return keyCombo;
    }
}

/*
This example produces results similar to the following output:

Enter a key ......... a
The hash code for the A key is 97.
Press the escape key (ESC) to quit, or any other key to continue.

Enter a key ......... S
The hash code for the SHIFT+S key is 83.
Press the escape key (ESC) to quit, or any other key to continue.

Enter a key .........
The hash code for the ALT+SHIFT+CTL+J key is 7.
Press the escape key (ESC) to quit, or any other key to continue.

*/

// This example demonstrates the ConsoleKeyInfo.GetHashCode() method.

open System
open System.Text

// The keyCombination function creates a string that specifies what
// key and what combination of shift, CTRL, and ALT modifier keys
// were pressed simultaneously.
let keyCombination (sourceCki: ConsoleKeyInfo) =
    let sb = StringBuilder()
    sb.Length <- 0
    if int sourceCki.Modifiers <> 0 then
        if int (sourceCki.Modifiers &&& ConsoleModifiers.Alt) <> 0 then
            sb.Append "ALT+" |> ignore
        if int (sourceCki.Modifiers &&& ConsoleModifiers.Shift) <> 0 then
            sb.Append "SHIFT+" |> ignore
        if int (sourceCki.Modifiers &&& ConsoleModifiers.Control) <> 0 then
            sb.Append "CTL+" |> ignore

    sourceCki.Key
    |> string
    |> sb.Append
    |> string

//
// The Console.TreatControlCAsInput property prevents this example from
// ending if you press CTL+C, however all other operating system keys and
// shortcuts, such as ALT+TAB or the Windows Logo key, are still in effect.
//
Console.TreatControlCAsInput <- true

let mutable cki1 = Unchecked.defaultof<ConsoleKeyInfo>

// Request that the user enter two key presses. A key press and any
// combination shift, CTRL, and ALT modifier keys is permitted.
while cki1.Key <> ConsoleKey.Escape do
    printf "\nEnter a key ......... " 
    cki1 <- Console.ReadKey false
    printfn ""

    let key1 = keyCombination cki1
    let hashCode = cki1.GetHashCode()
    printfn $"The hash code for the {key1} key is {hashCode}."

    printfn "Press the escape key (ESC) to quit, or any other key to continue."
    cki1 <- Console.ReadKey true

// Note: This example requires the Escape (Esc) key.
//
// This example produces results similar to the following output:
//
// Enter a key ......... a
// The hash code for the A key is 97.
// Press the escape key (ESC) to quit, or any other key to continue.
//
// Enter a key ......... S
// The hash code for the SHIFT+S key is 83.
// Press the escape key (ESC) to quit, or any other key to continue.
//
// Enter a key .........
// The hash code for the ALT+SHIFT+CTL+J key is 7.
// Press the escape key (ESC) to quit, or any other key to continue.

' This example demonstrates the ConsoleKeyInfo.GetHashCode() method.
Imports System.Text

Class Sample
    Public Shared Sub Main() 
        Dim k1 As String = vbCrLf & "Enter a key ......... "
        Dim key1 As String = ""
        Dim hashCodeFmt As String = "The hash code for the {0} key is {1}."
        Dim prompt As String = "Press the escape key (ESC) to quit, " & _
                               "or any other key to continue."
        Dim cki1 As ConsoleKeyInfo
        Dim hashCode As Integer = 0
        
        '
        ' The Console.TreatControlCAsInput property prevents this example from
        ' ending if you press CTL+C, however all other operating system keys and 
        ' shortcuts, such as ALT+TAB or the Windows Logo key, are still in effect. 
        '
        Console.TreatControlCAsInput = True
        
        ' Request that the user enter two key presses. A key press and any 
        ' combination shift, CTRL, and ALT modifier keys is permitted.
        Do
            Console.Write(k1)
            cki1 = Console.ReadKey(False)
            Console.WriteLine()
            '
            key1 = KeyCombination(cki1)
            hashCode = cki1.GetHashCode()
            Console.WriteLine(hashCodeFmt, key1, hashCode)
            '
            Console.WriteLine(prompt)
            cki1 = Console.ReadKey(True)
        Loop While cki1.Key <> ConsoleKey.Escape
    
    End Sub
     ' Note: This example requires the Escape (Esc) key.
    
    ' The KeyCombination() method creates a string that specifies what 
    ' key and what combination of shift, CTRL, and ALT modifier keys 
    ' were pressed simultaneously.
    Protected Shared Function KeyCombination(ByVal sourceCki As ConsoleKeyInfo) As String 
        Dim sb As New StringBuilder()
        sb.Length = 0
        Dim keyCombo As String
        If sourceCki.Modifiers <> 0 Then
            If(sourceCki.Modifiers And ConsoleModifiers.Alt) <> 0 Then
                sb.Append("ALT+")
            End If
            If(sourceCki.Modifiers And ConsoleModifiers.Shift) <> 0 Then
                sb.Append("SHIFT+")
            End If
            If(sourceCki.Modifiers And ConsoleModifiers.Control) <> 0 Then
                sb.Append("CTL+")
            End If
        End If
        sb.Append(sourceCki.Key.ToString())
        keyCombo = sb.ToString()
        Return keyCombo
    
    End Function 'KeyCombination
End Class

'
'This example produces results similar to the following output:
'
'Enter a key ......... a
'The hash code for the A key is 97.
'Press the escape key (ESC) to quit, or any other key to continue.
'
'Enter a key ......... S
'The hash code for the SHIFT+S key is 83.
'Press the escape key (ESC) to quit, or any other key to continue.
'
'Enter a key .........
'The hash code for the ALT+SHIFT+CTL+J key is 7.
'Press the escape key (ESC) to quit, or any other key to continue.
'

Remarks

The value returned by the GetHashCode method is not suitable for distinguishing one ConsoleKeyInfo object from another. If your application needs a unique hash code, override the GetHashCode method with your own method.