CryptoProvider.CanDecrypt 屬性

定義

命名空間:

System.Security.RightsManagement

組件:

WindowsBase.dll

取得值，指出使用者是否具有解密權限。

public:
 property bool CanDecrypt { bool get(); };

public bool CanDecrypt { get; }

member this.CanDecrypt : bool

Public ReadOnly Property CanDecrypt As Boolean

屬性值

Boolean

trueUseLicense如果 授與使用者解密的許可權，則為 ， false 否則為 。

範例

下列範例示範如何使用 CanDecrypt 屬性來判斷是否允許解密。

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 == true)
    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

備註

CanDecrypttrue如果系結至這個 CryptoProvider 的 UseLicense 會授與使用者讀取存取許可權，例如檢視、編輯、列印或擁有者，則傳回 。

另請參閱

• CanEncrypt
• Bind(SecureEnvironment)