GetPropertyGuid Method

Retrieves the Guid structure for any WIA property of type WiaVariableTypes.Clsid .

Syntax

Visual Basic
C#
WinRT C#
WinRT JavaScript
C++

public Guid GetPropertyGuid( 
   object item,
   string propertyIdName,
   WiaPropertyId propertyId
)

'Declaration
 
Public Function GetPropertyGuid( _
   ByVal item As Object, _
   ByVal propertyIdName As String, _
   ByVal propertyId As WiaPropertyId _
) As Guid

'Usage
 
Dim instance As WiaSession
Dim item As Object
Dim propertyIdName As String
Dim propertyId As WiaPropertyId
Dim value As Guid
 
value = instance.GetPropertyGuid(item, propertyIdName, propertyId)

public Guid GetPropertyGuid( 
   object item,
   string propertyIdName,
   WiaPropertyId propertyId
)

 function Leadtools.Wia.WiaSession.GetPropertyGuid( 
   item ,
   propertyIdName ,
   propertyId 
)

public:
Guid GetPropertyGuid( 
   Object^ item,
   String^ propertyIdName,
   WiaPropertyId propertyId
)

Parameters

item

Handle to the item which represents the item having the property. You can retrieve this parameter by either calling the GetRootItem method to get the device's root item itself or by enumerating the child items of the device through a call to EnumChildItems method.

propertyIdName

This string should contain the equivalent property Id string for the WIA property ID. Use the see GetPropertyIdString method to get this string for the property ID.

If you passed null for this parameter then the WIA toolkit will use the property ID passed through the third parameter propertyId; otherwise this parameters will be used whether or not you passed valid property ID through the propertyId parameter

propertyId

The property ID for the value being sought, for list of available property IDs see WiaPropertyId.

This parameter is required only if the second parameter "propertyIdName"is null; otherwise you can pass 0 for this parameter.

Return Value

The WIA GUID value.

Remarks

Any WIA property of type WiaVariableTypes.Clsid (for example, WiaPropertyId.ItemFormat ) returns a Guid structure. In order to retrieve this type of properties you need to call the function GetPropertyGuid.

For more information, refer to Managing WIA Sources.

Example

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Dim mySession As WiaSession
Public Sub GetPropertyGuidExample(ByVal parent As IWin32Window)
   If (Not WiaSession.IsAvailable(WiaVersion.Version1)) Then
      MessageBox.Show("WIA version 1.0 not installed.")
      Return
   End If

   mySession = New WiaSession()
   mySession.Startup(WiaVersion.Version1)

   Dim res As DialogResult = mySession.SelectDeviceDlg(parent, WiaDeviceType.Default, WiaSelectSourceFlags.NoDefault)
   If res <> DialogResult.OK Then
      MessageBox.Show("Error selecting WIA device.")
      mySession.Shutdown()
      Return
   End If

   Dim rootItem As Object = mySession.GetRootItem(Nothing)
   If Not rootItem Is Nothing Then
      AddHandler mySession.EnumItemsEvent, AddressOf session_EnumItemsEvent3

      mySession.EnumChildItems(rootItem)

      RemoveHandler mySession.EnumItemsEvent, AddressOf session_EnumItemsEvent3
   End If

   mySession.Shutdown()
End Sub

Private Sub session_EnumItemsEvent3(ByVal sender As Object, ByVal e As WiaEnumItemsEventArgs)
   Dim found As Boolean = False

   If Not e.Item Is Nothing Then
      ' Read the item category property (this property is only available for WIA 2.0).
      Dim sessionCategoryGuid As Guid = mySession.GetPropertyGuid(e.Item, Nothing, WiaPropertyId.ItemCategory)

      ' Find the related item category for the received GUID.
      Dim categoryGuid As Guid = wiaSession.GetCategoryGuid(WiaCategories.Feeder)
      If categoryGuid = sessionCategoryGuid Then ' the item is a Feeder.
         Console.WriteLine("Item category: Feeder")
         found = True
      End If

      If found = False Then
         categoryGuid = wiaSession.GetCategoryGuid(WiaCategories.FeederBack)
         If categoryGuid = sessionCategoryGuid Then ' the item is a Feeder.
            Console.WriteLine("Item category: FeederBack")
            found = True
         End If
      End If

      If found = False Then
         categoryGuid = wiaSession.GetCategoryGuid(WiaCategories.FeederFront)
         If categoryGuid = sessionCategoryGuid Then ' the item is a Feeder.
            Console.WriteLine("Item category: FeederFront")
            found = True
         End If
      End If

      If found = False Then
         categoryGuid = wiaSession.GetCategoryGuid(WiaCategories.Film)
         If categoryGuid = sessionCategoryGuid Then ' the item is a Feeder.
            Console.WriteLine("Item category: Film")
            found = True
         End If
      End If

      If found = False Then
         categoryGuid = wiaSession.GetCategoryGuid(WiaCategories.FinishedFile)
         If categoryGuid = sessionCategoryGuid Then ' the item is a Feeder.
            Console.WriteLine("Item category: FinishedFile")
            found = True
         End If
      End If

      If found = False Then
         categoryGuid = wiaSession.GetCategoryGuid(WiaCategories.Flatbed)
         If categoryGuid = sessionCategoryGuid Then ' the item is a Feeder.
            Console.WriteLine("Item category: Flatbed")
            found = True
         End If
      End If

      If found = False Then
         categoryGuid = wiaSession.GetCategoryGuid(WiaCategories.Folder)
         If categoryGuid = sessionCategoryGuid Then ' the item is a Feeder.
            Console.WriteLine("Item category: Folder")
            found = True
         End If
      End If

      If found = False Then
         categoryGuid = wiaSession.GetCategoryGuid(WiaCategories.Root)
         If categoryGuid = sessionCategoryGuid Then ' the item is a Feeder.
            Console.WriteLine("Item category: Root")
            found = True
         End If
      End If

      session.FreeItem(e.Item)
   End If
End Sub

WiaSession mySession;
public void GetPropertyGuidExample(IWin32Window parent)
{
   if (!WiaSession.IsAvailable(WiaVersion.Version1))
   {
      MessageBox.Show("WIA version 1.0 not installed.");
      return;
   }

   mySession = new WiaSession();
   mySession.Startup(WiaVersion.Version1);

   DialogResult res = mySession.SelectDeviceDlg(parent, WiaDeviceType.Default, WiaSelectSourceFlags.NoDefault);
   if (res != DialogResult.OK)
   {
      MessageBox.Show("Error selecting WIA device.");
      mySession.Shutdown();
      return;
   }

   object rootItem = mySession.GetRootItem(null);
   if (rootItem != null)
   {
      mySession.EnumItemsEvent += new EventHandler<WiaEnumItemsEventArgs>(wiaSession_EnumItemsEvent3);

      mySession.EnumChildItems(rootItem);

      mySession.EnumItemsEvent -= new EventHandler<WiaEnumItemsEventArgs>(wiaSession_EnumItemsEvent3);
   }

   mySession.Shutdown();
}

void wiaSession_EnumItemsEvent3(object sender, WiaEnumItemsEventArgs e)
{
   bool found = false;

   if (e.Item != null)
   {
      // Read the item category property (this property is only available for WIA 2.0).
      Guid sessionCategoryGuid = mySession.GetPropertyGuid(e.Item, null, WiaPropertyId.ItemCategory);

      // Find the related item category for the received Guid.
      Guid categoryGuid = WiaSession.GetCategoryGuid(WiaCategories.Feeder);
      if(categoryGuid == sessionCategoryGuid)   // the item is a Feeder.
      {
         Console.WriteLine("Item category: Feeder");
         found = true;
      }

      if (found == false)
      {
         categoryGuid = WiaSession.GetCategoryGuid(WiaCategories.FeederBack);
         if(categoryGuid == sessionCategoryGuid)   // the item is a Feeder.
         {
            Console.WriteLine("Item category: FeederBack");
            found = true;
         }
      }

      if (found == false)
      {
         categoryGuid = WiaSession.GetCategoryGuid(WiaCategories.FeederFront);
         if(categoryGuid == sessionCategoryGuid)   // the item is a Feeder.
         {
            Console.WriteLine("Item category: FeederFront");
            found = true;
         }
      }

      if (found == false)
      {
         categoryGuid = WiaSession.GetCategoryGuid(WiaCategories.Film);
         if(categoryGuid == sessionCategoryGuid)   // the item is a Feeder.
         {
            Console.WriteLine("Item category: Film");
            found = true;
         }
      }

      if (found == false)
      {
         categoryGuid = WiaSession.GetCategoryGuid(WiaCategories.FinishedFile);
         if(categoryGuid == sessionCategoryGuid)   // the item is a Feeder.
         {
            Console.WriteLine("Item category: FinishedFile");
            found = true;
         }
      }

      if (found == false)
      {
         categoryGuid = WiaSession.GetCategoryGuid(WiaCategories.Flatbed);
         if(categoryGuid == sessionCategoryGuid)   // the item is a Feeder.
         {
            Console.WriteLine("Item category: Flatbed");
            found = true;
         }
      }

      if (found == false)
      {
         categoryGuid = WiaSession.GetCategoryGuid(WiaCategories.Folder);
         if(categoryGuid == sessionCategoryGuid)   // the item is a Feeder.
         {
            Console.WriteLine("Item category: Folder");
            found = true;
         }
      }

      if (found == false)
      {
         categoryGuid = WiaSession.GetCategoryGuid(WiaCategories.Root);
         if(categoryGuid == sessionCategoryGuid)   // the item is a Feeder.
         {
            Console.WriteLine("Item category: Root");
            found = true;
         }
      }

      mySession.FreeItem(e.Item);
   }
}

Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

WiaSession Class
WiaSession Members
Startup Method
Shutdown Method
GetRootItem Method
EnumChildItems Method
GetProperties Method
SetProperties Method
GetPropertyBuffer Method
SetPropertyBuffer Method
GetPropertyLong Method
SetPropertyLong Method
GetPropertyString Method
SetPropertyString Method
SetPropertyGuid Method
GetPropertySystemTime Method
SetPropertySystemTime Method