One attributed block with different attribute names?!

[Anonymous]

Hi,

I’m trying to figure out what led to this bizarre situation:

I have a drawing with 6 attributed block insertions.

The block definition name for all 6 insertions is “dwgtitle1”.  

Some of these 6 blocks have an attribute whose name is “DWG#”, while the rest of the 6 blocks have the same attribute, but it’s named “PLAN#”.

How is this possible to have one block name in your drawing but there are 2 versions with different attributes.

Can BLOCKREPLACE do this?

When I do an ATTSYNC, it wipes out or resets the attribute value in some of the blocks.

Thanks for any insight!

[vinodkl]

Hi,

Is it possible to share the drawing?

[cadffm]

>"How is this possible"

Because attributes on blockreferences have NOTHING to do with your block(definition)!

Create a new blockreference by using command INSERT or by drag&drop, DesignCenter or which way you prefer

and autocad creates a blockreferenc which shows the block content except the none-constand attributdefinitions,

and attach attributes to this new blockreference, based on the current template= the none-constant attriutdefinitons of that block.

attributes are part of the blockreference, not of the block, otherwise it would be impossible to have different attribute values for each blockreference.

(constant attributdefinitions are not much more than simple (M)TEXT elements in the block(definition),

 so it is part of the block and it display for each blockreferenc identical - like circles and mtext and so on.

 So in fact: It doesn't exist "constant attributes', only contant attributdefinitions=ATTDEF)

Test:

1. Create a Block, with a line and a none-constand ATTDEF "A1"

insert one blockreference

with a line and a none-constand ATTDEF "A1"

2. BEDIT this Block, and add a none-constand ATTDEF "A2" and set the color to red

insert one blockreference

3. BEDIT this Block, and add a none-constand ATTDEF "A3" and delete attdef "A1, and set the color of "A2" to green

insert one blockreference

4. BEDIT this Block, and add a none-constand ATTDEF "A4" and delete attdefs  "A2" "A3"

and do NOT insert a blockreference.

5. SAVE the file now.

Compare all three blockreferences of the same block now.

And to write down "all things" - sorry, time ends now.

5. Use ATTSYNC

None-constant ATTDEFs are template to create blockreference, nothing more.

[Alfred.NESWADBA · Accepted solution]

Hi,

>> How is this possible to have one block name in your drawing

>> but there are 2 versions with different attributes.

Simply forgot to run ATTSYNC after editing the block.

E.g. a block "TABLE" is created, containing attribute "PRICE" ... insert this block 1 time. Now edit the block definition and change "PRICE" to "P", now again insert 1 block "TABLE" ... now you have 2 blocks, each having different attributes.

>> When I do an ATTSYNC, it wipes out or resets the attribute

>> value in some of the blocks.

It only wipes out those attributes where the inserted blocks have attributes that do not exist in the block-definition any more. Seems that someone has forgotten ATTSYNC multiple times or does not know what happens with attribute-values when attributes are renamed inside the block-definition (values are lost).

Whenever you rename attributes AutoCAD in the block-editor (and not using BATTMAN) AutoCAD does not know what to do with the value of attribute "PRICE" when an attribute with this name does not exist any more. That's what BATTMAN can do better.

- alfred -

[Anonymous]

Thanks to everyone for your input!

I did a few tests this morning - and it looks like this issue was caused by a legacy version of the block dwgtitle1 (whose attribute value used to be PLAN#) was pasted into the drawing with more recent blocks that have that same attribute named as DWG#. 

It's not uncommon for users to copy and paste details from drawings that are 15 years old - no matter how often I tell them to just go to the detail library which is more current.

I know the users aren't thinking to use ATTSYNC because it seems like a new revelation every time I tell them they they have to do that to update block insertions after they make changes to attributes in the block editor.

Oh well - sounds like a mandatory CAD Meeting is in order...

[scatalan]

every time I'm editing block I used PURGE to delete all an used blocks and etc. is that okay even I dont use ATTSYNC? Thanks in advance