Attribute manipulation with ActiveX

Is there any way (Using VLisp, NOT VBA) to search for an attribute containing a particular "TagString" value in a block reference without having to create a counter and cycle through each of the elements of the "safearray" extracted from the resulting "variant" that is returned from the ( vlax-invoke-method BlockObject "GetAttributes" ) command???

In other words, I have a block with multiple attributes, each with different tag strings. I want to search for a certain tag string value, then get the value stored in that attribute.

I can do what I want with a counter, but I'd like to know if there is any way to make ActiveX find that unique TagString FOR me without having to create the counter and increment it. The block I'm using has over 60 attributes in it, so parsing through the safearray's list of VLA Objects seems cumbersome to me. I was just hoping that there is an easier way to do this.

TIA

 

ooooooo, good question...
I've been wondering about this myself.

Awhile back, Vladimir Nesterovsky contributed the following code:

; Copyright 2002 by Vladimir Nesterovsky
; Free for use by any commercial entity with
; less then $100 million annual revenue.
; The Holy Graal of vla->lisp conversion? ;-)
(defun vnLispValue (value)
(cond
((= (type value) 'variant)
(vnLispValue
(variant-value value)
)
);_end case
((= (type value) 'safearray)
(mapcar
'vnLispValue
(safearray-value value)
)
);_end case
(T
value
);_end case
);_end cond
);_end defun


Which can be used to return a list of vla objects when used with
'GetAttributes...

(setq TargetAttrib_objlst
(vnLispValue
(vlax-invoke-method
_obj
'GetAttributes
)
)
)

Might the above help to track things down easier?
(I've been trying to work out a general find'in'da'list case for this
myself, rather than looping through the entire mess)

Any ideas?

Best regards,
David Kozina

containing a particular "TagString" value in a block reference without
having to create a counter and cycle through each of the elements of the
"safearray" extracted from the resulting "variant" that is returned from the
( vlax-invoke-method BlockObject "GetAttributes" ) command???

different tag strings. I want to search for a certain tag string value, then
get the value stored in that attribute.

way to make ActiveX find that unique TagString FOR me without having to
create the counter and increment it. The block I'm using has over 60
attributes in it, so parsing through the safearray's list of VLA Objects
seems cumbersome to me. I was just hoping that there is an easier way to do
this.

 

Untested... but might this work in conjunction with code I posted earlier?

(setq TargetAttrib_obj
(car
(vl-member-if
'(lambda (ele)
(eq
(vlax-get-property
ele
'TagString
)
<<YOURTAGSTRING>>
)
)
TargetAttrib_objlst
)
)
);_end setq

 

Something like this? AFAIK, there is no way to just get the attribute
similar to a collection ala (vla-item .........

(setq blk_ent (car (entsel "\nSelect block with attributes: ")))
(setq blk_vla (vlax-ename->vla-object blk_ent))
(setq atts (vlax-invoke blk_vla "getattributes")); this returns a list, NOT
a safearray
(mapcar '(lambda(x)
(if (= (vla-get-tagstring x) "TEST2")
(vla-put-textstring x "Found it!")
)
)
atts)

Jeff

containing a particular "TagString" value in a block reference without
having to create a counter and cycle through each of the elements of the
"safearray" extracted from the resulting "variant" that is returned from the
( vlax-invoke-method BlockObject "GetAttributes" ) command???

different tag strings. I want to search for a certain tag string value, then
get the value stored in that attribute.

way to make ActiveX find that unique TagString FOR me without having to
create the counter and increment it. The block I'm using has over 60
attributes in it, so parsing through the safearray's list of VLA Objects
seems cumbersome to me. I was just hoping that there is an easier way to do
this.

 

So, putting it all together...
perhaps this would work? (Again, untested)

hth,
David Kozina

; Find Specific Attribute Reference using Tag String Identifier
(defun djkGetAttRefTagObject
(Block_obj ; Block object containing attributes
Tag_str ; Attribute TagString
/
;
)
; begin
(car
(vl-member-if
'(lambda (ele)
(eq
(vlax-get-property
ele
'TagString
)
Tag_str
)
)
(vnLispValue
(vlax-invoke-method
Block_obj
'GetAttributes
)
)
)
)
; end
);_end defun

 

Thanks for the response, Jeff.

When I implemented ( vlax-invoke-method ... ) I get a variant as the result. Does omission of the "-method" return a different type of VLA Object? If so, that's helpful to know.

I will give a variation of your code a try.

 

David,

Thanks so much for your response. I will take a good look at your code and give it at try. I'll let you know if I'm sucessful with it.

Thanks again!

 

Well, the (vlax-invoke obj "getattributes") returns a standard list of
vla-objects. In this sample, my block had 4 attributes.

(#<VLA-OBJECT IAcadAttributeReference 08bc6954> #<VLA-OBJECT
IAcadAttributeReference 08bc6834> #<VLA-OBJECT IAcadAttributeReference
08bc67c4> #<VLA-OBJECT IAcadAttributeReference 08bc2394>)

Jeff

result. Does omission of the "-method" return a different type of VLA
Object? If so, that's helpful to know.

 

I've been doing some minimal testing and it does seem to do what *I* need it
to do.
YMMV.

Thanks for posing the question Nick, I needed to review that particular
section of code which has been stinking up things around here for some time
now.

(FYI --- I was using an even more bogus method of finding a specific
attribute tag by making the idiotic ASSumption that they would be the LAST
tags in the retrieved list. <gagging> Desperation drives men to desperate
acts, eh? I'm SO ashamed.)

But I would like to know if there is a neater trick to doing this sort of
thing.

Best regards,
David Kozina

give it at try. I'll let you know if I'm sucessful with it.

 

Hi Nick

Visit my homepage -> Free Stuff and search for VxGetAtts/VxSetAtts...

Cheers

 

Thank you, Juerg!

 

Live and learn, eh?

Thanks for letting me "borrow your brain", Jeff.

 

Hi Nick

Glad to help you...

Cheers