You can redefine all instances of a block within the current drawing. To redefine a block that was created in the current drawing, you create a new block using the same name. You can update all the blocks in the current drawing by redefining the block. If the block was inserted from a separate drawing file that was subsequently updated, reinsert that block to update all other instances in the current drawing.
To redefine a block in the current drawing
Advanced experience level
The block is immediately redefined, and all instances of the block in the drawing are updated. The entities you select for inclusion in the block are removed from the drawing, because they are now part of the block.
TIP To restore the original entities to the drawing while retaining the new block, type undelete or oops.
You can update all instances of a block inserted from a separate drawing by reinserting the drawing.
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