Since the introduction of the new level system in MicroStation, levels can be deleted. Given the situation, it may be difficult to understand why a given level can not be deleted.
The general rule is that a level that is used by graphical data will appear as "bold" in the level list. When a level is not bold, the level should be able to be deleted by simply deleting it in Level Manager, however, there are times when a level will not delete even when it seems apparent that it is not used.
General Note for specifying level names in key ins:In case the level name that you want to specify contains spaces, always use double quotes when entering the name.Example:Level name in the Level Manager is shown as: Roof of house, make sure to enter:"Roof of house"
When a level is encountered that appears to be unused but will not be deleted, the first thing to do is try to find out where the level may be used.
Use the Key-in: LEVEL USAGE <level name>.
The message center should return the following: Level usage for : <File name>, <Model name>: <Level name>
Open message center and highlight the message to see the message details:
Used in Models : <Potential model name>Used in Cell Definitions : <Potential cell definition name>Used in Dim Styles : <Potential Dimension style name>
Message center dialog showing the details of "level usage" Key-in.
The details will list where the level is being used which can be one or more of the 3 listed categories.
How to delete the level
If level usage reports that it is used in a cell definition(s), then the file probably contains shared cell definitions that contain elements that use the level but none of the cells are placed actively in the file. If the shared cell definitions are determined to not be needed, they can be deleted.
Use the Key-in: DELETE SCDEFS NAMED|ANONYMOUS|ALL
NAMED - will delete the unused cell definition that has a name.ANONYMOUS - will delete all the unused cell definitions that do not have a name.ALL - will delete all unused cell definitions.
Check the message center to see if any shared cells were deleted. If the shared cell(s) was deleted the level usage for this level should not report that it is not being used. Assuming that the level is not used in the other two categories, level Manager should also report that the level is no longer bold. The level should now be able to be deleted.
How to delete the level: If the level usage reports that the level is used in a dimension style, it simply means the listed dimension style has this level for the dimension line.
To see this:
Dimension Lines category with-in the Dimension Styles dialog.
In order to delete the level, this dimension setting will need to be either disabled or the level will need to be changed. Repeat these steps for any other listed dimension styles for this level. From there, Assuming that the level is not used in the other two categories, Level Manger should no longer report the level to be bold. The level should now be able to be deleted.
How to delete the level: If the level usage reports that the level is used in a model, it generally means there are graphical elements in the given model that are using this level. This is the most common occurrence. This can normally be handled by turning off the display all the levels in the model except the one that is to be deleted to see what data is using the level. The decision can be made to either delete the contents of the level or move the contents to another level.
However there are occurrences where the level appears to be used but does not "show" graphical data in the view. There is a specific documented situation where this can happen.
Here is an example of that situation: When placing Patterns that are not associated to the boundary, MicroStation creates the hatch lines as expected, but also creates a hidden text element that is used to keep the linkages of the pattern. This element is needed when using the "Change Pattern" tool on a non-associated pattern or hatch. In MicroStation V8 2004 Edition (08.05.00.64 or later), these text elements, also know as "Pattern control elements" are placed on the default level. Prior versions were placing them on the active level. If a file is encountered that has un-associative patterns or hatches that were placed in a version prior to V8 2004 Edition, it may contain "invisible" text elements on the level that can not be graphically selected and deleted.
There are some key-in commands that can help with clearing up the level, if graphically deleting the elements is not an option.
Key-ins that are helpful for manipulating all elements on a given level:
LEVEL ELEMENT MOVE [DEST:<level name>] <level name>
Example: LEVEL ELEMENT MOVE DEST:test01 test02 This will move the contents of level "test02" to "test01". If a destination level is not specified, the contents of the source level will be moved to the default level.
LEVEL ELEMENT DELETE <level name>
Example: LEVEL ELEMENT DELETE DEST:test01 This will delete the contents of level "test01".
LEVEL PURGE [DEST:<level name>] <level name>
Example: LEVEL PURGE DEST:test01 test02 This will move all the contents of "test02" to "test01" and delete "test02". If a destination level is not specified, the contents of the source level will be moved to the default level.
Using one or a combination of the key-ins should work to get the level clear for deletion.