ActiveX and VBA Developer's Guide > Advanced Drawing and Organizational Techniques > Use Blocks and Attributes > Work with Attributes > 
Create Attribute Definitions and Attribute References
 
 
 

To create an attribute reference, first you must create an attribute definition on a block by using the AddAttribute method. This method requires six values as input: the height of the attribute text, the Attribute mode, a prompt string, the insertion point, the tag string, and the default attribute value.

The mode value is optional. There are five constants you can enter to specify the Attribute mode:

acAttributeModeNormal

Specifies that the current mode of each attribute is maintained.

acAttributeModeInvisible

Specifies that attribute values won't appear when you insert the block. The ATTDISP command overrides the Invisible mode.

acAttributeModeConstant

Gives attributes a fixed value for block insertions.

acAttributeModeVerify

Prompts you to verify that the attribute value is correct when you insert the block.

acAttributeModePreset

Sets the attribute to its default value when you insert a block containing a present attribute. The value cannot be edited in this mode.

You can enter none, any combination, or all of the options. To specify a combination of options, add the constants together. For example, you can enter acAttributeModeInvisible + acAttributeModeConstant.

The prompt string appears when a block containing the attribute is inserted. The default for this string is the Tag string. Input acAttributeModeConstant for the mode to disable the prompt.

The tag string identifies each occurrence of the attribute. You can use any characters except spaces or exclamation points. AutoCAD changes lowercase letters to uppercase.

Once the attribute definition is defined in a block, whenever you insert the block using the InsertBlock method you can specify a different value for the attribute reference.

An attribute definition is associated to the block upon which it is created. Attribute definitions created on model space or paper space are not considered attached to any given block.

Define an attribute definition

This example creates a block and then adds an attribute to the block. The block is then inserted into the drawing.

Sub Ch10_CreatingAnAttribute()

	' Define the block

	Dim blockObj As AcadBlock

	Dim insertionPnt(0 To 2) As Double

	insertionPnt(0) = 0

	insertionPnt(1) = 0

	insertionPnt(2) = 0

	Set blockObj = ThisDrawing.Blocks.Add _

					 (insertionPnt, "BlockWithAttribute")




	' Add an attribute to the block




	Dim attributeObj As AcadAttribute




	Dim height As Double




	Dim mode As Long




	Dim prompt As String




	Dim insertionPoint(0 To 2) As Double




	Dim tag As String




	Dim value As String




	height = 1




	mode = acAttributeModeVerify




	prompt = "New Prompt"




	insertionPoint(0) = 5




	insertionPoint(1) = 5




	insertionPoint(2) = 0




	tag = "New Tag"




	value = "New Value"




	Set attributeObj = blockObj.AddAttribute(height, mode, _




						prompt, insertionPoint, tag, value)




	' Insert the block, creating a block reference




	' and an attribute reference




	Dim blockRefObj As AcadBlockReference




	insertionPnt(0) = 2




	insertionPnt(1) = 2




	insertionPnt(2) = 0




	Set blockRefObj = ThisDrawing.ModelSpace.InsertBlock _




			 (insertionPnt, "BlockWithAttribute", 1#, 1#, 1#, 0)




End Sub