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SecureString Constructors

Definition

Initializes a new instance of the SecureString class.

Overloads

SecureString()

Initializes a new instance of the SecureString class.

SecureString(Char*, Int32)

Initializes a new instance of the SecureString class from a subarray of Char objects.

This constructor is not CLS-compliant. The CLS-compliant alternative is SecureString().

SecureString()

Source:
SecureString.cs
Source:
SecureString.cs
Source:
SecureString.cs

Initializes a new instance of the SecureString class.

public:
 SecureString();
public SecureString ();
Public Sub New ()

Exceptions

An error occurred while protecting or unprotecting the value of this instance.

This operation is not supported on this platform.

Examples

The following example uses the default (or parameterless) constructor to instantiate a new SecureString object. It then calls the AppendChar method to add an array of characters to it.

using namespace System;
using namespace System::Security;

int main(array<System::String ^> ^args)
{
   // Define the string value to assign to a new secure string.
   Char chars[4] = { 't', 'e', 's', 't' };
   // Instantiate the secure string.
   SecureString^ testString = gcnew SecureString();
   // Assign the character array to the secure string.
   for each (Char ch in chars)
   {
      testString->AppendChar(ch);
   }   
   // Display secure string length.
   Console::WriteLine("The length of the string is {0} characters.", 
                        testString->Length);

   delete testString;
   return 0;
}
// The example displays the following output:
//      The length of the string is 4 characters.
using System;
using System.Security;

public class Example
{
   public static void Main()
   {
      // Define the string value to assign to a new secure string.
      char[] chars = { 't', 'e', 's', 't' };
      // Instantiate the secure string.
      SecureString testString = new SecureString();
      // Assign the character array to the secure string.
      foreach (char ch in chars)
         testString.AppendChar(ch);      
      // Display secure string length.
      Console.WriteLine("The length of the string is {0} characters.", 
                        testString.Length);
      testString.Dispose();
   }
}
// The example displays the following output:
//      The length of the string is 4 characters.
Imports System.Security

Module Example
   Public Sub Main()
      ' Define the string value to assign to a new secure string.
      Dim chars() As Char = { "t"c, "e"c, "s"c, "t"c }
      ' Instantiate the secure string.
      Dim testString As SecureString = New SecureString()
      ' Assign the character array to the secure string.
      For Each ch As char In chars
         testString.AppendChar(ch)
      Next         
      ' Display secure string length.
      Console.WriteLine("The length of the string is {0} characters.", _ 
                        testString.Length)
      testString.Dispose()
   End Sub
End Module
' The example displays the following output:
'      The length of the string is 4 characters.

The following example creates a SecureString object from the value of a String object.

using namespace System;
using namespace System::Security;

int main(array<System::String ^> ^args)
{
   // Define the string value to be assigned to the secure string.
   String^ initString = "TestString";
   // Instantiate the secure string.
   SecureString^ testString = gcnew SecureString();
   // Assign the character array to the secure string.
   for each (Char ch in initString)
   {
      testString->AppendChar(ch);
   }   
   // Display secure string length.
   Console::WriteLine("The length of the string is {0} characters.", 
                        testString->Length);

   delete testString;
   return 0;
}
// The example displays the following output:
//      The length of the string is 10 characters.
using System;
using System.Security;

public class Example
{
   public static void Main()
   {
      // Define the string value to be assigned to the secure string.
      string initString = "TestString";
      // Instantiate the secure string.
      SecureString testString = new SecureString();
      // Use the AppendChar method to add each char value to the secure string.
      foreach (char ch in initString)
         testString.AppendChar(ch);
         
      // Display secure string length.
      Console.WriteLine("The length of the string is {0} characters.", 
                        testString.Length);
      testString.Dispose();
   }
}
// The example displays the following output:
//      The length of the string is 10 characters.
Imports System.Security

Module Example
   Public Sub Main()
      ' Define the string value to be assigned to the secure string.
      Dim initString As String = "TestString"
      ' Instantiate the secure string.
      Dim testString As SecureString = New SecureString()
      ' Use the AppendChar method to add each char value to the secure string.
      For Each ch As Char In initString
         testString.AppendChar(ch)
      Next   
      ' Display secure string length.
      Console.WriteLine("The length of the string is {0} characters.", _ 
                        testString.Length)
      testString.Dispose()
   End Sub
End Module
' The example displays the following output:
'      The length of the string is 10 characters.

Applies to

SecureString(Char*, Int32)

Source:
SecureString.cs
Source:
SecureString.cs
Source:
SecureString.cs

Important

This API is not CLS-compliant.

Initializes a new instance of the SecureString class from a subarray of Char objects.

This constructor is not CLS-compliant. The CLS-compliant alternative is SecureString().

public:
 SecureString(char* value, int length);
[System.CLSCompliant(false)]
public SecureString (char* value, int length);
[System.CLSCompliant(false)]
[System.Security.SecurityCritical]
public SecureString (char* value, int length);
[<System.CLSCompliant(false)>]
new System.Security.SecureString : nativeptr<char> * int -> System.Security.SecureString
[<System.CLSCompliant(false)>]
[<System.Security.SecurityCritical>]
new System.Security.SecureString : nativeptr<char> * int -> System.Security.SecureString

Parameters

value
Char*

A pointer to an array of Char objects.

length
Int32

The number of elements of value to include in the new instance.

Attributes

Exceptions

value is null.

length is less than zero or greater than 65,536.

An error occurred while protecting or unprotecting the value of this secure string.

This operation is not supported on this platform.

Examples

The following example instantiates a new SecureString object by passing its constructor a pointer to a character array.

using namespace System;
using namespace System::Security;

int main(array<System::String ^> ^args)
{
   SecureString^ testString;
   // Define the string value to assign to a new secure string.
   Char chars[4] = { 't', 'e', 's', 't' };
   // Instantiate a new secure string.
   Char* pChars = &chars[0];

   testString = gcnew SecureString(pChars, sizeof(chars)/sizeof(chars[0]));

   // Display secure string length.
   Console::WriteLine("The length of the string is {0} characters.", 
                        testString->Length);
   delete testString;
   return 0;
}
// The example displays the following output:
//      The length of the string is 4 characters.
using System;
using System.Security;

public class Example
{
   unsafe public static void Main()
   {
      SecureString testString;
      // Define the string value to assign to a new secure string.
      char[] chars = { 't', 'e', 's', 't' };

      // Instantiate a new secure string.
      fixed(char* pChars = chars)
      {
         testString = new SecureString(pChars, chars.Length);
      }
      // Display secure string length.
      Console.WriteLine("The length of the string is {0} characters.", 
                        testString.Length);
      testString.Dispose();
   }
}
// The example displays the following output:
//      The length of the string is 4 characters.

Remarks

This constructor initializes the new SecureString object to the number of characters in value specified by length; the value of the instance is then encrypted.

In C#, this constructor is defined only in the context of unsafe code.

Applies to