IPermission.Union(IPermission) Metode

Definisi

Ruang nama:

System.Security

Rakitan:

System.Runtime.dll

Membuat izin yang merupakan gabungan izin saat ini dan izin yang ditentukan.

public:
 System::Security::IPermission ^ Union(System::Security::IPermission ^ target);

public System.Security.IPermission? Union (System.Security.IPermission? target);

abstract member Union : System.Security.IPermission -> System.Security.IPermission

Public Function Union (target As IPermission) As IPermission

Parameter

target

IPermission

Izin untuk digabungkan dengan izin saat ini. Jenisnya harus sama dengan izin saat ini.

Mengembalikan

IPermission

Izin baru yang mewakili gabungan izin saat ini dan izin yang ditentukan.

Pengecualian

ArgumentException

Parameter target bukan null dan bukan tipe yang sama dengan izin saat ini.

Contoh

Contoh kode berikut menunjukkan penerapan Union metode . Contoh kode ini adalah bagian dari contoh yang lebih besar yang disediakan untuk IPermission kelas .

    // Return a new object that contains the union of 'this' and 'target'.
    // Note: You do not have to implement this method. 
    // If you do not, the version
    // in CodeAccessPermission does this:
    //    1. If target is not null, a NotSupportedException is thrown.
    //    2. If target is null, then Copy is called and 
    //       the new object is returned.
public:
    virtual IPermission^ Union(IPermission^ target) override
    {
        // If 'target' is null, then return a copy of 'this'.
        if (target == nullptr)
        {
            return Copy();
        }

        // Both objects must be the same type.
        SoundPermission^ soundPerm = VerifyTypeMatch(target);

        // If 'this' or 'target' are unrestricted, 
        // return a new unrestricted permission.
        if (specifiedAsUnrestricted || soundPerm->specifiedAsUnrestricted)
        {
            return Clone(true, SoundPermissionState::PlayAnySound);
        }

        // Return a new object with the calculated, unioned permission value.
        return Clone(false, (SoundPermissionState)
            Math::Max((int) stateFlags, (int) soundPerm->stateFlags));
    }

// Return a new object that contains the union of 'this' and 'target'.
// Note: You do not have to implement this method. If you do not, the version
// in CodeAccessPermission does this:
//    1. If target is not null, a NotSupportedException is thrown.
//    2. If target is null, then Copy is called and the new object is returned.
public override IPermission Union(IPermission target)
{
    // If 'target' is null, then return a copy of 'this'.
    if (target == null) return Copy();

    // Both objects must be the same type.
    SoundPermission soundPerm = VerifyTypeMatch(target);

    // If 'this' or 'target' are unrestricted, return a new unrestricted permission.
    if (m_specifiedAsUnrestricted || soundPerm.m_specifiedAsUnrestricted)
        return Clone(true, SoundPermissionState.PlayAnySound);

    // Return a new object with the calculated, unioned permission value.
    return Clone(false, (SoundPermissionState)
        Math.Max((Int32)m_flags, (Int32)soundPerm.m_flags));
}

' Return a new object that contains the union of 'this' and 'target'.
' Note: You do not have to implement this method. If you do not, the version
' in CodeAccessPermission does this:
'    1. If target is not null, a NotSupportedException is thrown.
'    2. If target is null, then Copy is called and the new object is returned.
Public Overrides Function Union(ByVal target As IPermission) As IPermission
    ' If 'target' is null, then return a copy of 'this'.
    If target Is Nothing Then
        Return Copy()
    End If
    ' Both objects must be the same type.
    Dim soundPerm As SoundPermission = VerifyTypeMatch(target)

    ' If 'this' or 'target' are unrestricted, return a new unrestricted permission.
    If m_specifiedAsUnrestricted OrElse soundPerm.m_specifiedAsUnrestricted Then
        Return Clone(True, SoundPermissionState.PlayAnySound)
    End If
    ' Return a new object with the calculated, unioned permission value.
    Return Clone(False, CType(Math.Max(CType(m_flags, Int32), CType(soundPerm.m_flags, Int32)), SoundPermissionState))

End Function 'Union

Keterangan

Hasil panggilan ke Union adalah izin yang mewakili semua operasi yang diwakili oleh izin saat ini dan izin yang ditentukan. Setiap permintaan yang melewati izin melewati serikat mereka.

Pernyataan berikut harus benar untuk semua implementasi Union metode. X dan Y mewakili IPermission objek yang bukan null.

• X. Union(X) mengembalikan objek yang memiliki nilai yang sama dengan X.

• X. Union(Y) mengembalikan objek yang memiliki nilai yang sama dengan objek yang dikembalikan oleh Y. Union(X).

• X. Union(null) mengembalikan objek yang memiliki nilai yang sama dengan X.