This documentation is archived and is not being maintained.
KeySizes Class
Visual Studio 2008
Determines the set of valid key sizes for the symmetric cryptographic algorithms.
Assembly: mscorlib (in mscorlib.dll)
The following example shows the use of members of the KeySizes class.
Imports System Imports System.Security.Cryptography Public Class Form1 Inherits System.Windows.Forms.Form ' Event handler for Run button. Private Sub Button1_Click( _ ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click tbxOutput.Cursor = Cursors.WaitCursor tbxOutput.Text = "" ' Initializes a new instance of the KeySizes class with the ' specified key values. Dim MinSize As Integer = 64 Dim MaxSize As Integer = 1024 Dim SkipSize As Integer = 64 Dim keySizes As New KeySizes(MinSize, MaxSize, SkipSize) ' Show the values of the keys. ShowKeys(New KeySizes(0) {keySizes}, "Custom Keys") ' Create a new symmetric algorithm and display its key values. Dim rijn As SymmetricAlgorithm = SymmetricAlgorithm.Create() WriteLine("rijn.blocksize:" + rijn.BlockSize.ToString()) ShowKeys(rijn.LegalKeySizes, rijn.ToString()) ' Create a new RSA algorithm and display its key values. Dim rsaCSP As New RSACryptoServiceProvider(384) WriteLine("RSACryptoServiceProvider KeySize = " + _ rsaCSP.KeySize.ToString()) ShowKeys(rsaCSP.LegalKeySizes, rsaCSP.ToString()) ' Reset the cursor and conclude application. WriteLine("This sample completed successfully;" + _ " press Exit to continue.") tbxOutput.Cursor = Cursors.Default End Sub ' Display specified KeySize properties to output textbox. Private Sub ShowKeys( _ ByVal KeySizes() As KeySizes, _ ByVal objectName As String) ' Retrieve the first KeySizes in the array. Dim firstKeySize As KeySizes = KeySizes(0) ' Retrieve the minimum key size in bits. Dim minKeySize As Integer = firstKeySize.MinSize ' Retrieve the maximum key size in bits. Dim maxKeySize As Integer = firstKeySize.MaxSize ' Retrieve the interval between valid key size in bits. Dim skipKeySize As Integer = firstKeySize.SkipSize WriteLine("KeySizes retrieved from the " + objectName + " object.") WriteLine("Minimum key size bits: " + minKeySize.ToString()) WriteLine("Maximum key size bits: " + maxKeySize.ToString()) WriteLine("Interval between key size bits: " + skipKeySize.ToString()) WriteLine("") End Sub ' Display the message to the textbox with a carriage return and line feed. Private Sub WriteLine(ByVal message As String) tbxOutput.AppendText(message + vbCrLf) End Sub ' Event handler for Exit button. Private Sub Button2_Click( _ ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button2.Click Application.Exit() End Sub #Region " Windows Form Designer generated code " Public Sub New() MyBase.New() 'This call is required by the Windows Form Designer. InitializeComponent() 'Add any initialization after the InitializeComponent() call End Sub 'Form overrides dispose to clean up the component list. Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean) If disposing Then If Not (components Is Nothing) Then components.Dispose() End If End If MyBase.Dispose(disposing) End Sub 'Required by the Windows Form Designer Private components As System.ComponentModel.IContainer 'NOTE: The following procedure is required by the Windows Form Designer 'It can be modified using the Windows Form Designer. 'Do not modify it using the code editor. Friend WithEvents Panel2 As System.Windows.Forms.Panel Friend WithEvents Panel1 As System.Windows.Forms.Panel Friend WithEvents Button1 As System.Windows.Forms.Button Friend WithEvents Button2 As System.Windows.Forms.Button Friend WithEvents tbxOutput As System.Windows.Forms.RichTextBox <System.Diagnostics.DebuggerStepThrough()> _ Private Sub InitializeComponent() Me.Panel2 = New System.Windows.Forms.Panel Me.Button1 = New System.Windows.Forms.Button Me.Button2 = New System.Windows.Forms.Button Me.Panel1 = New System.Windows.Forms.Panel Me.tbxOutput = New System.Windows.Forms.RichTextBox Me.Panel2.SuspendLayout() Me.Panel1.SuspendLayout() Me.SuspendLayout() ' 'Panel2 ' Me.Panel2.Controls.Add(Me.Button1) Me.Panel2.Controls.Add(Me.Button2) Me.Panel2.Dock = System.Windows.Forms.DockStyle.Bottom Me.Panel2.DockPadding.All = 20 Me.Panel2.Location = New System.Drawing.Point(0, 320) Me.Panel2.Name = "Panel2" Me.Panel2.Size = New System.Drawing.Size(616, 64) Me.Panel2.TabIndex = 1 ' 'Button1 ' Me.Button1.Dock = System.Windows.Forms.DockStyle.Right Me.Button1.Font = New System.Drawing.Font("Microsoft Sans Serif", _ 9.0!, _ System.Drawing.FontStyle.Regular, _ System.Drawing.GraphicsUnit.Point, _ CType(0, Byte)) Me.Button1.Location = New System.Drawing.Point(446, 20) Me.Button1.Name = "Button1" Me.Button1.Size = New System.Drawing.Size(75, 24) Me.Button1.TabIndex = 2 Me.Button1.Text = "&Run" ' 'Button2 ' Me.Button2.Dock = System.Windows.Forms.DockStyle.Right Me.Button2.Font = New System.Drawing.Font("Microsoft Sans Serif", _ 9.0!, _ System.Drawing.FontStyle.Regular, _ System.Drawing.GraphicsUnit.Point, _ CType(0, Byte)) Me.Button2.Location = New System.Drawing.Point(521, 20) Me.Button2.Name = "Button2" Me.Button2.Size = New System.Drawing.Size(75, 24) Me.Button2.TabIndex = 3 Me.Button2.Text = "E&xit" ' 'Panel1 ' Me.Panel1.Controls.Add(Me.tbxOutput) Me.Panel1.Dock = System.Windows.Forms.DockStyle.Fill Me.Panel1.DockPadding.All = 20 Me.Panel1.Location = New System.Drawing.Point(0, 0) Me.Panel1.Name = "Panel1" Me.Panel1.Size = New System.Drawing.Size(616, 320) Me.Panel1.TabIndex = 2 ' 'tbxOutput ' Me.tbxOutput.AccessibleDescription = _ "Displays output from application." Me.tbxOutput.AccessibleName = "Output textbox." Me.tbxOutput.Dock = System.Windows.Forms.DockStyle.Fill Me.tbxOutput.Location = New System.Drawing.Point(20, 20) Me.tbxOutput.Name = "tbxOutput" Me.tbxOutput.Size = New System.Drawing.Size(576, 280) Me.tbxOutput.TabIndex = 1 Me.tbxOutput.Text = "Click the Run button to run the application." ' 'Form1 ' Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15) Me.ClientSize = New System.Drawing.Size(616, 384) Me.Controls.Add(Me.Panel1) Me.Controls.Add(Me.Panel2) Me.Name = "Form1" Me.Text = "KeySizes" Me.Panel2.ResumeLayout(False) Me.Panel1.ResumeLayout(False) Me.ResumeLayout(False) End Sub #End Region End Class ' ' 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 ' ' rijn.blocksize:128 ' 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 ' ' RSACryptoServiceProvider KeySize = 384 ' 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 ' ' This sample completed successfully; press Exit to continue.
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Show: