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**SetFilter(**// expression //[//, id //] **), VIRTUAL**

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| **SetFilter** | Specifies a filter for the active sort order. |
| **expression** | A string constant, variable, EQUATE, or expression that contains a FILTER expression. See //FILTER// in the //Language Reference// for more information. If //expression //is null (' ') , setFilter deletes any existing filter with same //id// . |
| //id// | A string constant, variable, EQUATE, or expression that uniquely identifies (and prioritizes) the filter so you can apply multiple filter conditions, and so you can replace or remove filter conditions with subsequent calls to SetFilter. If omitted, the filter gets a default id so that subsequent calls to SetFilter with no //id //replace the filter //expression //set by prior calls to SetFilter with no //id//. |

The **SetFilter **method specifies a filter for the active sort order. When the filter is applied, the view only includes those elements whose //expression //evaluates to true.

The //id //parameter lets you specify multiple filter //expression//s or replace a specific //expression //by its //id//. If you set several //expression//s, each with a unique id, then all those //expression//s must evaluate to true to include an item in the result set. The //id// parameter must begin with a number.

The ViewManager evaluates the //expression//s in //id// order (highest number first, lowest number last), so it is efficient to prioritize //expression//s most likely to fail; for example:

**MyView.SetFilter('TaxPayer=True','1Tax')       !low priority expression**

**MyView.SetFilter('LotteryWinner=True','9Lot')  !high priority expression**

**!evaluates as: (LotteryWinner=True) AND (TaxPayer=True)**

The ApplyFilter and ApplyRange methods apply the active sort order's filter. The SetSort method sets the active sort order.

**Implementation:**

The ViewManager uses the //id //to indicate the priority of the //expression//. The priority is implemented by sorting the list of filter expressions by the //id//. The //id //is truncated after 30 characters. If omitted, //id //defaults to '5 Standard' which specifies a medium priority filter that is replaced by any subsequent calls to SetFilter with //id //omitted (or '5 Standard') and with the same active sort order.

Each call to SetFilter with a unique //id// parameter adds to the filter expression for the active sort order. Multiple expressions added in this fashion are joined with the boolean AND operator.

The SetFilter method adds the filter //id //and //expression //to the Order property.

**Example:**

** MyView.AddSortOrder(ORD:ByOrder)                       !order no. sort (1)**

** MyView.SetFilter('(ORD:OrdNo=CUST:OrdNo)','1OrderNo')  !filter on OrderNo**

** MyView.SetFilter('(ORD:Date='&amp;TODAY()&amp;')','1Date')     !AND on date. Date test applied**

**                                                        !first because it sorts first**

** MyView.AddSortOrder(ORD:ByName)                        !customer name sort (2)**

** MyView.SetFilter('CUST:Name[1]=''A''')                 !filter on cust name**

** !program code**

** MyView.SetSort(2)                                      !sort by customer name**

** MyView.SetFilter('CUST:Name[1]=''J''')                 !new filter on cust name**

**                                                        !replaces prior name filter**

**See Also:**     [[addsortorder  add a sort order .htm|AddSortOrder]], [[order  sort  range limit  and filter information .htm|Order]]