ConsoleKeyInfo::GetHashCode Method ()

 

Returns the hash code for the current ConsoleKeyInfo object.

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

public:
virtual int GetHashCode() override

Return Value

Type: System::Int32

A 32-bit signed integer hash code.

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.

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.

*/

.NET Framework
Available since 2.0
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