Using ATTIN and ATTOUT together, you can quickly make changes to attribute values for selected block references.

Command: ATTIN
Enter input filename: Use the File dialog box to find and import data from the desired file

If attribute values have been modified, the changes are incorporated into the drawing's block insertions. The input file must be in the format generated by ATTOUT, though it does not have to have been created by ATTOUT

Usage:
When you execute the ATTIN command, it reads through the input file and processes each line. If it finds a block with the same handle and block name as the row it is processing, it applies the attribute changes, if any, to that block. When it has processed all the blocks it can find, it prompts you to assign the remaining data interactively. If you choose Yes, it lists each row's data on the command line and allows you to select a block to apply the attribute to, press ENTER to go to the next row, or press ESC to exit.

File Format:

The output file written by ATTOUT is a tab-delimited, ASCII file that is suitable for editing by most database and spreadsheet programs. Microsoft Excel works well for this task. Just make sure that when you save your changes you save them in a tab-delimited ASCII format; otherwise the ATTIN command will not be able to import from the file.

The first row in the file contains column headers that identify the data to ATTIN. The first two columns are labeled HANDLE and BLOCKNAME. These columns are optional to ATTIN, but their presence allows the attribute data to be read from this file and inserted into the drawing automatically. If these columns are not present, the user is prompted to supply this data as ATTIN is processing the file.

The remaining columns in the file are labeled with attribute tags as they appear in the drawing. Because database programs often require that column headers be unique, numbers are added to duplicate attribute tags to ensure uniqueness. For example, the header row in a file created by ATTOUT might look like this:

HANDLE  BLOCKNAME  MYTAG  MYOTHERTAG  MYTAG(1)

The remaining rows in the file represent a single block insert object and the values of each of its respective attributes.

Because there is a column for each attribute from all selected blocks, there will almost certainly be attribute labels that do not apply to a specific block. These labels are indicated with the string "<>" in the cells that do not apply. Thus, in a file containing the preceding header row example, the row for a block that contains only the attribute MYTAG might look like this:

HANDLE  BLOCKNAME  MYTAG  MYOTHERTAG  MYTAG(1)
E1	MYBLOCK1   Data1  <> 	<>

The "<>" indicates that this attribute does not apply to the current block and that a cell is an attribute that does apply, but that it is empty at this time.