> For the complete documentation index, see [llms.txt](https://boxlang.ortusbooks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/cache/cachefilter.md).

# CacheFilter

This method creates a cache filter that can be used to operate on a cache instance and its keys.

The filter can be used to clear, get, or remove keys from the cache.

All filters must be adhere to the {@link ICacheKeyFilter} interface.

Example:

```
 cache().clear( cacheFilter( "foo*" ) );
 cache().clear( cacheFilter( ".*foo.*", true ) );

 You can also create your own custom cache filter by using a closure/lambda that
 accepts a {@code
 Key
 } and returns a boolean.

 Example:

  cache().clear( key -> key.getName().startsWith( "foo" ) ); cache().clear( key -> key.getName().matches( ".*foo.*" ) ); 
Method Signature
CacheFilter(filter=[string], useRegex=[boolean])
Arguments



























Examples
Filter cache entries by criteria
cachePut( "key1", "value1", 60 );cachePut( "key2", "value2", 60 );filtered = cacheFilter( ( key, entry ) => key == "key1" );writeOutput( filtered.len() );
Result: 1
Related





```


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