' This example demonstrates the AppendChar,
' InsertAt, RemoveAt, SetAt, and Clear methods.
Imports System
Imports System.Security
Class Sample
Public Shared Sub Main()
Dim msg1 As String = " SecureString = {0}" & vbCrLf & " Length = {1}" & vbCrLf
Dim msg2 As String = "This example demonstrates the effect of the AppendChar, InsertAt," & vbCrLf & _
"RemoveAt, SetAt, and Clear methods on the value of a SecureString" & vbCrLf & _
"object. This example simulates the value of the object because the" & vbCrLf & _
"actual value is encrypted." & vbCrLf
Dim ss As New SecureString()
'
' This sample modifies the contents of a SecureString, ss, in
' several steps. After each step, the length and simulated value of ss
' are displayed. The actual value of ss is encrypted.
'
Console.WriteLine(msg2)
Console.WriteLine("1) The initial value of the SecureString object:")
Console.WriteLine(msg1, """""", ss.Length)
Console.WriteLine("2) AppendChar: Append 'a' to the value:")
ss.AppendChar("a"c)
Console.WriteLine(msg1, """a""", ss.Length)
Console.WriteLine("3) AppendChar: Append 'X' to the value:")
ss.AppendChar("X"c)
Console.WriteLine(msg1, """aX""", ss.Length)
Console.WriteLine("4) AppendChar: Append 'c' to the value:")
ss.AppendChar("c"c)
Console.WriteLine(msg1, """aXc""", ss.Length)
Console.WriteLine(("5) InsertAt: Insert 'd' at the end of the value (equivalent" & vbCrLf & " to AppendChar):"))
ss.InsertAt(ss.Length, "d"c)
Console.WriteLine(msg1, """aXcd""", ss.Length)
Console.WriteLine("6) RemoveAt: Remove the last character ('d') from the value:")
ss.RemoveAt(3)
Console.WriteLine(msg1, """aXc""", ss.Length)
Console.WriteLine("7) SetAt: Set the second character ('X') of the value to 'b':")
ss.SetAt(1, "b"c)
Console.WriteLine(msg1, """abc""", ss.Length)
Console.WriteLine("8) Clear: Delete the value of the SecureString object:")
ss.Clear()
Console.WriteLine(msg1, """""", ss.Length)
End Sub 'Main
End Class 'Sample
'
'This code example produces the following results:
'
'This example demonstrates the effect of the AppendChar, InsertAt,
'RemoveAt, SetAt, and Clear methods on the value of a SecureString
'object. This example simulates the value of the object because the
'actual value is encrypted.
'
'1) The initial value of the SecureString object:
' SecureString = ""
' Length = 0
'
'2) AppendChar: Append 'a' to the value:
' SecureString = "a"
' Length = 1
'
'3) AppendChar: Append 'X' to the value:
' SecureString = "aX"
' Length = 2
'
'4) AppendChar: Append 'c' to the value:
' SecureString = "aXc"
' Length = 3
'
'5) InsertAt: Insert 'd' at the end of the value (equivalent
' to AppendChar):
' SecureString = "aXcd"
' Length = 4
'
'6) RemoveAt: Remove the last character ('d') from the value:
' SecureString = "aXc"
' Length = 3
'
'7) SetAt: Set the second character ('X') of the value to 'b':
' SecureString = "abc"
' Length = 3
'
'8) Clear: Delete the value of the SecureString object:
' SecureString = ""
' Length = 0
'
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