C/S应用程序权限设计(3)

窗体访问权限的控制

此类权限就比较好控制了,你有权限就可以打开窗体,没有权限就不能打开.由于系统中所有的窗体都是基于FormBase继承而来的,那就有了集中控制权限的基础.首先创建了一个属性类,只能作用于类上,代码如下:

 

'''  -----------------------------------------------------------------------------
'''  Project     : Lily.ComponentFramework
'''  Class     : ComponentFramework.PermissionAttribute
'''  
'''  -----------------------------------------------------------------------------
'''   <summary>
'''  类访问许可属性定义
'''   </summary>
'''   <remarks>
'''   </remarks>
'''   <history>
'''      [zqonline]    2007-03-27    Created
'''   </history>
'''  -----------------------------------------------------------------------------
< AttributeUsage(AttributeTargets.Class) >   Public   Class  PermissionAttribute
     Inherits  System.Attribute
     Private  md_name  As   String   =   String .Empty
     Private  md_guid  As   String   =   String .Empty
     Private  md_description  As   String   =   String .Empty
     Public   Sub   New ( ByVal  name  As   String ,  ByVal  guid  As   String ,  ByVal  description  As   String )
         Me .md_name  =  name
         Me .md_guid  =  guid
         Me .md_description  =  description
     End Sub
     '''  -----------------------------------------------------------------------------
     '''   <summary>
     '''  名称.
     '''   </summary>
     '''   <value></value>
     '''   <remarks>
     '''   </remarks>
     '''   <history>
     '''      [zqonline]    2006-12-25    Created
     '''   </history>
     '''  -----------------------------------------------------------------------------
     Public   ReadOnly   Property  Name()  As   String
         Get
             Return   Me .md_name
         End   Get
     End Property
     '''  -----------------------------------------------------------------------------
     '''   <summary>
     '''  唯一标识.
     '''   </summary>
     '''   <value></value>
     '''   <remarks>
     '''   </remarks>
     '''   <history>
     '''      [zqonline]    2006-12-25    Created
     '''   </history>
     '''  -----------------------------------------------------------------------------
     Public   ReadOnly   Property  Guid()  As   String
         Get
             Return   Me .md_guid
         End   Get
     End Property
     '''  -----------------------------------------------------------------------------
     '''   <summary>
     '''  返回描述.
     '''   </summary>
     '''   <value></value>
     '''   <remarks>
     '''   </remarks>
     '''   <history>
     '''      [zqonline]    2006-12-25    Created
     '''   </history>
     '''  -----------------------------------------------------------------------------
     Public   ReadOnly   Property  Description()  As   String
         Get
             Return   Me .md_description
         End   Get
     End Property
End Class

 

其中最主要的就是guid,每一个窗体都对应一个guid,guid是可以唯一的,窗体的名称,确不可以.如果某一个窗体需要进行权限控制,只需把PermissionAttribute作用于窗体上即可!那什么时候,进行权限判断呢,在基类窗体FormBase有如下代码:

实例化时进行权限判断

     Public   Sub   New ()
         MyBase .New()

         ' 该调用是 Windows 窗体设计器所必需的。
        InitializeComponent()

         ' 在 InitializeComponent() 调用之后添加任何初始化
         If   Not   Me .IsLoad  Then
            GC.SuppressFinalize( Me )
             Throw   New  PermissionException( " 当前用户没有进行此项操作的权限。 " )
         End   If

     End Sub

 

 

    '''  -----------------------------------------------------------------------------
     '''   <summary>
     '''  返回当前用户是否有权限加载.
     '''   </summary>
     '''   <returns></returns>
     '''   <remarks>
     '''   </remarks>
     '''   <history>
     '''      [zqonline]    2006-12-24    Created
     '''   </history>
     '''  -----------------------------------------------------------------------------
     Public   Overridable   Function  IsLoad()  As   Boolean   Implements  IFormManager.IsLoad
         If   Not   Me .PermissionAttribute  Is   Nothing   Then
             Return  Lily.ComponentFramework.ComponentManager.Permission.Has( Me .PermissionAttribute)
         Else
             Return   True
         End   If
     End Function

 

这个主要是判断当前窗体是否具有PermissionAttribute属性,如果没有,说明不需要进行权限控制

     Private  md_pa  As  PermissionAttribute
     < Browsable( False ) >   Public   ReadOnly   Property  PermissionAttribute()  As  PermissionAttribute
         Get
             If   Me .md_pa  Is   Nothing   Then
                 Dim  objs  As   Object ()  =   Me .GetType.GetCustomAttributes( GetType (Lily.ComponentFramework.PermissionAttribute),  True )
                 If   Not  objs  Is   Nothing   AndAlso  objs.Length  >   0   Then
                     Dim  v  As  Lily.ComponentFramework.PermissionAttribute  =   CType (objs( 0 ), Lily.ComponentFramework.PermissionAttribute)
                     If   Not  v.Name  Is   Nothing   AndAlso  v.Name.Length  >   0  _
                             AndAlso   Not  v.Guid  Is   Nothing  _
                             AndAlso  v.Guid.Length  >   0   Then
                         Me .md_pa  =  v
                     End   If
                 End   If
             End   If
             Return   Me .md_pa
         End   Get
     End Property

 

 

待续