IPermission.Intersect(IPermission) Metode

Definisi

Ruang nama:

System.Security

Rakitan:

System.Runtime.dll

Membuat dan mengembalikan izin yang merupakan persimpangan izin saat ini dan izin yang ditentukan.

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

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

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

Public Function Intersect (target As IPermission) As IPermission

Parameter

target

IPermission

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

Mengembalikan

IPermission

Izin baru yang mewakili persimpangan izin saat ini dan izin yang ditentukan. Izin baru ini adalah null jika persimpangan kosong.

Pengecualian

ArgumentException

Parameter target bukan null dan bukan instans dari kelas yang sama dengan izin saat ini.

Contoh

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

    // Return a new object that contains the intersection 
    // of 'this' and 'target'.
public:
    virtual IPermission^ Intersect(IPermission^ target) override
    {
        // If 'target' is null, return null.
        if (target == nullptr)
        {
            return nullptr;
        }

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

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

        // Calculate the intersected permissions. 
        // If there are none, return null.
        SoundPermissionState minimumPermission = (SoundPermissionState)
            Math::Min((int) stateFlags, (int) soundPerm->stateFlags);
        if ((int)minimumPermission == 0)
        {
            return nullptr;
        }

        // Return a new object with the intersected permission value.
        return Clone(false, minimumPermission);
    }

// Return a new object that contains the intersection of 'this' and 'target'.
public override IPermission Intersect(IPermission target)
{
    // If 'target' is null, return null.
    if (target == null) return null;

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

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

    // Calculate the intersected permissions. If there are none, return null.
    SoundPermissionState val = (SoundPermissionState)
        Math.Min((Int32)m_flags, (Int32)soundPerm.m_flags);
    if (val == 0) return null;

    // Return a new object with the intersected permission value.
    return Clone(false, val);
}

' Return a new object that contains the intersection of 'this' and 'target'.
Public Overrides Function Intersect(ByVal target As IPermission) As IPermission
    ' If 'target' is null, return null.
    If target Is Nothing Then
        Return Nothing
    End If
    ' Both objects must be the same type.
    Dim soundPerm As SoundPermission = VerifyTypeMatch(target)

    ' If 'this' and 'target' are unrestricted, return a new unrestricted permission.
    If m_specifiedAsUnrestricted AndAlso soundPerm.m_specifiedAsUnrestricted Then
        Return Clone(True, SoundPermissionState.PlayAnySound)
    End If
    ' Calculate the intersected permissions. If there are none, return null.
    Dim val As SoundPermissionState = CType(Math.Min(CType(m_flags, Int32), CType(soundPerm.m_flags, Int32)), SoundPermissionState)
    If val = 0 Then
        Return Nothing
    End If
    ' Return a new object with the intersected permission value.
    Return Clone(False, val)

End Function 'Intersect

Keterangan

Persimpangan dua izin adalah izin yang menjelaskan serangkaian operasi yang mereka jelaskan secara umum. Hanya permintaan yang melewati kedua izin asli yang akan melewati persimpangan.

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

• X. Intersect(X) mengembalikan nilai yang sama dengan X.

• X. Intersect(Y) mengembalikan nilai yang sama dengan Y. Intersect(X).

• X. Intersect(null) mengembalikan null.