KeySizes Class
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KeySizes Class

 

Determines the set of valid key sizes for the symmetric cryptographic algorithms.

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

System.Object
  System.Security.Cryptography.KeySizes

[ComVisibleAttribute(true)]
public sealed class KeySizes

NameDescription
System_CAPS_pubmethodKeySizes(Int32, Int32, Int32)

Initializes a new instance of the KeySizes class with the specified key values.

NameDescription
System_CAPS_pubpropertyMaxSize

Specifies the maximum key size in bits.

System_CAPS_pubpropertyMinSize

Specifies the minimum key size in bits.

System_CAPS_pubpropertySkipSize

Specifies the interval between valid key sizes in bits.

NameDescription
System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

The following example shows the use of members of the KeySizes class.

using System;
using System.Security.Cryptography;

namespace Contoso
{
    class KeySizesMembers
    {
        [STAThread]
        static void Main(string[] args)
        {
            // Initializes a new instance of the KeySizes class with the
            // specified key values.
            int minSize = 64;
            int maxSize = 1024;
            int skipSize = 64;
            KeySizes keySizes = new KeySizes(minSize, maxSize, skipSize);

            // Show the values of the keys.
            ShowKeys(new KeySizes[1]{keySizes}, "Custom Keys");

            // Create a new symmetric algorithm and display its key values.
            SymmetricAlgorithm rijn = SymmetricAlgorithm.Create();
            ShowKeys(rijn.LegalKeySizes, rijn.ToString());
            Console.WriteLine("rijn.blocksize:" + rijn.BlockSize);

            // Create a new RSA algorithm and display its key values.
            RSACryptoServiceProvider rsaCSP = 
                new RSACryptoServiceProvider(384);
            ShowKeys(rsaCSP.LegalKeySizes, rsaCSP.ToString());
            Console.WriteLine("RSACryptoServiceProvider KeySize = " + 
                rsaCSP.KeySize);

            Console.WriteLine("This sample completed successfully; " +
                "press Enter to exit.");
            Console.ReadLine();
        }

        // Display specified KeySize properties to the console.
        private static void ShowKeys(KeySizes[] keySizes, string objectName)
        {
            // Retrieve the first KeySizes in the array.
            KeySizes firstKeySize = keySizes[0];

            // Retrieve the minimum key size in bits.
            int minKeySize = firstKeySize.MinSize;

            // Retrieve the maximum key size in bits.
            int maxKeySize = firstKeySize.MaxSize;

            // Retrieve the interval between valid key size in bits.
            int skipKeySize = firstKeySize.SkipSize;

            Console.Write("\n KeySizes retrieved from the ");
            Console.WriteLine(objectName + " object.");
            Console.WriteLine("Minimum key size bits: " + minKeySize);
            Console.WriteLine("Maximum key size bits: " + maxKeySize);
            Console.WriteLine("Interval between key size bits: " + 
                skipKeySize);
        }
	}
}
//
// This sample produces the following output:
//
// KeySizes retrieved from the Custom Keys object.
// Minimum key size bits: 64
// Maximum key size bits: 1024
// Interval between key size bits: 64
// 
// KeySizes retrieved from the System.Security.Cryptography.RijndaelManaged
// object.
// Minimum key size bits: 128
// Maximum key size bits: 256
// Interval between key size bits: 64
// rijn.blocksize:128
// 
// KeySizes retrieved from the
// System.Security.Cryptography.RSACryptoServiceProvider object.
// Minimum key size bits: 384
// Maximum key size bits: 16384
// Interval between key size bits: 8
// RSACryptoServiceProvider KeySize = 384
// This sample completed successfully; press Enter to exit.

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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