RoleProvider.DeleteRole(String, Boolean) 方法

定義

命名空間:

System.Web.Security

組件:

System.Web.ApplicationServices.dll

為已設定的 applicationName 移除資料來源中的角色。

public:
 abstract bool DeleteRole(System::String ^ roleName, bool throwOnPopulatedRole);

public abstract bool DeleteRole (string roleName, bool throwOnPopulatedRole);

abstract member DeleteRole : string * bool -> bool

Public MustOverride Function DeleteRole (roleName As String, throwOnPopulatedRole As Boolean) As Boolean

參數

roleName

String

要刪除的角色名稱。

throwOnPopulatedRole

Boolean

如果 true，且如果 roleName 有一或多個成員則擲回例外狀況，且不刪除 roleName。

傳回

Boolean

如果成功刪除角色，即為 true；否則為 false。

範例

下列程式代碼範例示範 方法的範例實作 DeleteRole 。

public override bool DeleteRole(string rolename, bool throwOnPopulatedRole)
{
  if (!RoleExists(rolename))
  {
    throw new ProviderException("Role does not exist.");
  }

  if (throwOnPopulatedRole && GetUsersInRole(rolename).Length > 0)
  {
    throw new ProviderException("Cannot delete a populated role.");
  }

  OdbcConnection conn = new OdbcConnection(connectionString);
  OdbcCommand cmd = new OdbcCommand("DELETE FROM Roles "  +
                                    " WHERE Rolename = ? AND ApplicationName = ?", conn);

  cmd.Parameters.Add("@Rolename", OdbcType.VarChar, 255).Value = rolename;
  cmd.Parameters.Add("@ApplicationName", OdbcType.VarChar, 255).Value = ApplicationName;

  OdbcCommand cmd2 = new OdbcCommand("DELETE FROM UsersInRoles "  +
                                     " WHERE Rolename = ? AND ApplicationName = ?", conn);

  cmd2.Parameters.Add("@Rolename", OdbcType.VarChar, 255).Value = rolename;
  cmd2.Parameters.Add("@ApplicationName", OdbcType.VarChar, 255).Value = ApplicationName;

  try
  {
    conn.Open();

    cmd2.ExecuteNonQuery();
    cmd.ExecuteNonQuery();
  }
  catch (OdbcException)
  {
    // Handle exception.

    return false;
  }
  finally
  {
    conn.Close();      
  }

  return true;
}

Public Overrides Function DeleteRole(ByVal rolename As String, ByVal throwOnPopulatedRole As Boolean) As Boolean
    If Not RoleExists(rolename) Then
        Throw New ProviderException("Role does not exist.")
    End If

    If throwOnPopulatedRole AndAlso GetUsersInRole(rolename).Length > 0 Then
        Throw New ProviderException("Cannot delete a populated role.")
    End If

    Dim conn As OdbcConnection = New OdbcConnection(connectionString)
    Dim cmd As OdbcCommand = New OdbcCommand("DELETE FROM Roles " & _
                                             " WHERE Rolename = ? AND ApplicationName = ?", conn)

    cmd.Parameters.Add("@Rolename", OdbcType.VarChar, 255).Value = rolename
    cmd.Parameters.Add("@ApplicationName", OdbcType.VarChar, 255).Value = ApplicationName

    Dim cmd2 As OdbcCommand = New OdbcCommand("DELETE FROM UsersInRoles " & _
                                              " WHERE Rolename = ? AND ApplicationName = ?", conn)

    cmd2.Parameters.Add("@Rolename", OdbcType.VarChar, 255).Value = rolename
    cmd2.Parameters.Add("@ApplicationName", OdbcType.VarChar, 255).Value = ApplicationName

    Try
        conn.Open()

        cmd2.ExecuteNonQuery()
        cmd.ExecuteNonQuery()
    Catch e As OdbcException
        ' Handle exception.

        Return False
    Finally
        conn.Close()
    End Try

    Return True
End Function

備註

DeleteRole由 DeleteRole 類別的 Roles 和 DeleteRole 方法呼叫，以從所設定 ApplicationName的數據源中刪除指定的角色。

當您從資料來源中刪除角色時，請確定您也會刪除使用者名稱與所設定 applicationName已刪除角色之間的任何關聯。

如果 為 truethrowOnPopulatedRole ，且 參數所roleName識別的角色有一或多個成員，請擲回 ProviderException ，且不會刪除角色。 如果 throwOnPopulatedRole 為 false，則刪除角色是否空白。

如果指定的角色名稱不存在、為 null或 是空字串，建議您的提供者擲回例外狀況。

另請參閱

• 實作角色提供者