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CryptoProvider.CanDecrypt Property

  • Reference

Definition

Namespace:
System.Security.RightsManagement
Assembly:
WindowsBase.dll

Gets a value that indicates whether the user has rights to decrypt.

public:
 property bool CanDecrypt { bool get(); };
public bool CanDecrypt { get; }
member this.CanDecrypt : bool
Public ReadOnly Property CanDecrypt As Boolean

Property Value

Boolean

true if the UseLicense grants the user rights to decrypt; otherwise, false.

Examples

The following example shows how to use the CanDecrypt property to determine if decryption is allowed.

ShowStatus("   Binding UseLicense with the SecureEnvironment" +
         "\n       to obtain the CryptoProvider.");
CryptoProvider cryptoProvider = useLicense.Bind(_secureEnv);

ShowStatus("   Obtaining BoundGrants.");
ReadOnlyCollection<ContentGrant> grants =
    cryptoProvider.BoundGrants;

rightsBlockTitle.Text = "Rights - " + Filename(useLicenseFile);
rightsBlock.Text = "GRANTS LIST\n-----------------\n";
foreach (ContentGrant grant in grants)
{
    rightsBlock.Text += "USER:  " + grant.User.Name + " [" +
        grant.User.AuthenticationType + "]\n";
    rightsBlock.Text += "RIGHT: " + grant.Right.ToString() + "\n";
    rightsBlock.Text += "    From:  " + grant.ValidFrom + "\n";
    rightsBlock.Text += "    Until: " + grant.ValidUntil + "\n";
}

if (cryptoProvider.CanDecrypt)
    ShowStatus("   Decryption granted.");
else
    ShowStatus("   CANNOT DECRYPT!");

ShowStatus("   Binding UseLicense with the SecureEnvironment" & vbLf & "       to obtain the CryptoProvider.")
Dim cryptoProvider As CryptoProvider = useLicense.Bind(_secureEnv)

ShowStatus("   Obtaining BoundGrants.")
Dim grants As ReadOnlyCollection(Of ContentGrant) = cryptoProvider.BoundGrants

rightsBlockTitle.Text = "Rights - " & Filename(useLicenseFile)
rightsBlock.Text = "GRANTS LIST" & vbLf & "-----------------" & vbLf
For Each grant As ContentGrant In grants
    rightsBlock.Text &= "USER:  " & grant.User.Name & " [" & grant.User.AuthenticationType & "]" & vbLf
    rightsBlock.Text &= "RIGHT: " & grant.Right.ToString() & vbLf
    rightsBlock.Text &= "    From:  " & grant.ValidFrom & vbLf
    rightsBlock.Text &= "    Until: " & grant.ValidUntil & vbLf
Next grant

If cryptoProvider.CanDecrypt = True Then
    ShowStatus("   Decryption granted.")
Else
    ShowStatus("   CANNOT DECRYPT!")
End If

Remarks

CanDecrypt returns true if the UseLicense bound to this CryptoProvider grants the user read access rights such as View, Edit, Print, or Owner.

Applies to

See also