~~Title: Filter~~
<pageheader/>

The **Filter** object lets you create a [[:file_operations:filtered_operations:textual_filters|textual filter]] of the type used by the **Find** tool and commands such as **Copy** to control recursive operations.

Use the **[[dopusfactory]].Filter** method to create a new filter object. Once you have a **Filter** object you can:

  * Use the **[[item]].MatchFilter** method to see if a file or folder matches the filter.
  * Apply the filter to a command with the **[[command]].SetFilter** method.

<commandtable columns="3" id="cmdtable_1">
$$ Property Name
$$ Return Type
$$ Description
$$ lasterror
$$ //object://**[[filterparseerror]]**
$$ If //valid// returns **False** you can use this property to discover information about the error.
$$ valid
$$ //bool//
$$ Returns **True** if the filter was created successfully (i.e. no errors were encountered in parsing the filter text).
</commandtable>


<commandtable columns="4" id="cmdtable_2">
$$ Method Name
$$ **Arguments**
$$ Return Type
$$ Description
$$ Add
$$ <string:clause>\\
or <object:**Filter**>\\
[<string:conjunction>]
$$ //bool//
$$ Adds a clause to the filter. If provided as a string, the clause will be parsed and the method returns **True** if parsing was successful. If parsing fails, use the **lasterror** property to find out why. Alternatively, you can add another **Filter** object.

The //clause// string must be a fully formed [[:file_operations:filtered_operations:textual_filters|textual filter]] clause. For example, <code>size match > 2 mb</code>

The optional //conjunction// string lets you choose whether the clause is joined via **and** or **or**. If not specified, the default is **and**.
$$ Clear
$$ //none//
$$ //none//
$$ Clears the contents of the filter.
$$ Set
$$ <string:clause>\\
or <object:**Filter**>\\
$$ //bool//
$$ Initialises the filter with either a string or the contents of an existing **Filter** object. If provided as a string, the clause will be parsed and the method returns **True** if parsing was successful. If parsing fails, use the **lasterror** property to find out why. 
</commandtable>