Types of Filter

There are several different types of filter, and they are used as follows.

• Class Filter - used to include or exclude entire classes of items

If you want to exclude an entire item class or limit the display to an item class (such as all text items, or all Polygon items), use the class based filter.

• Feature Filter - used to include or exclude certain feature types

To exclude an entire feature type, or limit the display to one feature type only, use the feature filter. This filter can be based on the feature types of many different datasets (e.g. TIGER/Line95, Meridian, etc.).

Feature filters can also include or exclude items with no feature code.

• Property Filter - Used to include or exclude items based on their properties

If you want to include or exclude items on the basis of a property value, use the property filter. For instance, you could limit the display to just those items whose pen or brush is Green. Properties can also be combined in expressions.

• Compound Filter - Used to include or exclude Items by combining filters

Use the compound filter option to combine other filters.

The following is a list of all available Filter classes:

• Class Filter
  
• Combined Class/Property
  
• Compound Filter
  
• Feature Filter
  
• Layer Filter
  
• List of item IDs
  
• OGC Filter
  
• Property Filter
  
• Value-list Filter
  

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