filter

Method which triggers filter command for the column with UniqueName (set on the server) passed as a first argument. The second argument should be value to compare (or two values separated by [space] for between filter pattern) or an empty string for EqualTo, NoFilter, IsNull, etc. The last third argument has to be a value from the Telerik.Web.UI.GridFilterFunction enumeration which internally recognizes the filter criteria that should be applied. All server-side filtering capabilities of RadGrid are applicable here as well. See the topic describing the fireCommand method for further details.

filter(colUniqueName, valueToCompare, filterFunction, shouldUpdateFilterControl)
colUniqueName	String	The UniqueName of the column that will be filtered.
valueToCompare	Optional argument (String, Integer, etc.)	The value which will be used for the comparison against the entire set of data through the filter criteria.
filterFunction	Enumeration value	The filter pattern that will be applied.
shouldUpdateFilterControl	Boolean (Optional)	Determines whether the filter control will be updated with the relevant filter value applied by the grid filter expression. The default value is false.

Example:

function RemoveFilter() {
    var masterTable = $find("<%= RadGrid1.ClientID %>").get_masterTableView();
    masterTable.filter("OrderID", "", Telerik.Web.UI.GridFilterFunction.NoFilter);
}

function ApplyGreaterThanFilter() {
    var masterTable = $find("<%= RadGrid1.ClientID %>").get_masterTableView();
    masterTable.filter("OrderID", 10254, Telerik.Web.UI.GridFilterFunction.GreaterThan, true);
}

function ApplyBetweenFilter() {
    var masterTable = $find("<%= RadGrid1.ClientID %>").get_masterTableView();
    masterTable.filter("OrderID", "10256 10260", Telerik.Web.UI.GridFilterFunction.Between, true);
}

Telerik.Web.UI.GridFilterFunction enumeration

Internal integer value	Public value
0	NoFilter
1	Contains
2	DoesNotContain
3	StartsWith
4	EndsWith
5	EqualTo
6	NotEqualTo
7	GreaterThan
8	LessThan
9	GreaterThanOrEqualTo
10	LessThanOrEqualTo
11	Between
12	NotBetween
13	IsEmpty
14	NotIsEmpty
15	IsNull
16	NotIsNull
17	Custom

When using client-side binding to RadClientDataSource, you need to add filter expressions directly to the data source through the dataSourceReference.get_filterExpressions().add() method. You can find similar example in the ClientDataSource - Filtering live demo.