A collection of Telerik.Web.UI.GridFilterExpression objects. Represents
the filter expressions applied for the grid instance.
The toString() javascript method executed
over this collection will return SQL string representation of all filter expressions concatenated
by 'AND' reserved words. While filter expressions toString() method will create SQL syntax
representing current grid filtering, you can also take advantage of the
toDynamicLinq() javascript method which will create LINQ expression that can be
used directly with Dynamic LINQ library.
Furthermore, you can also utilize the toList() javascript method
in order to pass an array of items (representing the filter expression elements) to the server and operate
with them using GridFilterExpression server object.
When the toString() method is executed over a
particular Telerik.Web.UI.GridFilterExpression object, it will return SQL string
representation of the expression using the Telerik.Web.UI.GridFilterFunctionsSqlFormat
enumeration values:
CopyJavaScript
Telerik.Web.UI.GridFilterFunctionsSqlFormat = function()
{
var _knownFilterFunctions = {};
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.Contains] = "[{0}] LIKE '%{1}%'";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.DoesNotContain] = "[{0}] NOT LIKE '%{1}%'";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.StartsWith] = "[{0}] LIKE '{1}%'";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.EndsWith] = "[{0}] LIKE '%{1}'";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.EqualTo] = "[{0}] = {1}";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.NotEqualTo] = "[{0}] <> {1}";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.GreaterThan] = "[{0}] > {1}";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.LessThan] = "[{0}] < {1}";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.GreaterThanOrEqualTo] = "[{0}] >= {1}";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.LessThanOrEqualTo] = "[{0}] <= {1}";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.Between] = "([{0}] >= {1}) AND ([{0}] <= {2})";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.NotBetween] = "([{0}] < {1}) OR ([{0}] > {2})";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.IsEmpty] = "[{0}] = ''";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.NotIsEmpty] = "[{0}] <> ''";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.IsNull] = "[{0}] IS NULL";
_knownFilterFunctions[Telerik.Web.UI.GridFilterFunction.NotIsNull] = "NOT ([{0}] IS NULL)";
return _knownFilterFunctions;
};
The toDynamicLinq() javascript method can be executed over a single
Telerik.Web.UI.GridFilterExpression object, which will generate LINQ expression
that can be used directly with Dynamic LINQ library.
Additionally, there is another method - toDataService(), which again can be
executed over a single Telerik.Web.UI.GridFilterExpression object and will
generate an expression that can be recognized by ADO.NET Data Services.
There is one more method - toOql() for filter expressions which can be used
if you want to bind the grid client-side directly to Telerik OpenAccess OQL query. Here are some code
blocks which illustrates sample approach:
CopyJavaScript
{
var tableView = sender.get_masterTableView();
var sortParameterName = sender.ClientSettings.DataBinding.SortParameterName;
var filterParameterName = sender.ClientSettings.DataBinding.FilterParameterName;
args.get_methodArguments()[sortParameterName] = tableView.get_sortExpressions().toString();
args.get_methodArguments()[filterParameterName] = tableView.get_filterExpressions().toOql();
}
CopyC#
public IList GetData(int startRowIndex, int maximumRows, string sortExpression, string filterExpression)
{
string oqlQuery = "SELECT * FROM CustomerExtent";
if (!String.IsNullOrEmpty(filterExpression))
{
oqlQuery = String.Format(" {0} WHERE {1} ", oqlQuery, filterExpression);
}
if (!String.IsNullOrEmpty(sortExpression))
{
oqlQuery = String.Format(" {0} ORDER BY {1} ", oqlQuery, sortExpression);
}
IList data = db.GetObjectScope().GetOqlQuery(oqlQuery).Execute();
List<object> list = new List<object>();
for (int i = 0; i < Math.Min(maximumRows, data.Count); i++)
{
list.Add(data[i + startRowIndex]);
}
Session["Count"] = data.Count;
return list;
}CopyVB.NET
Public Function GetData(ByVal startRowIndex As Integer, ByVal maximumRows As Integer, ByVal sortExpression As String, ByVal filterExpression As String) As IList
Dim oqlQuery As String = "SELECT * FROM CustomerExtent"
If Not [String].IsNullOrEmpty(filterExpression) Then
oqlQuery = [String].Format(" {0} WHERE {1} ", oqlQuery, filterExpression)
End If
If Not [String].IsNullOrEmpty(sortExpression) Then
oqlQuery = [String].Format(" {0} ORDER BY {1} ", oqlQuery, sortExpression)
End If
Dim data As IList = db.GetObjectScope().GetOqlQuery(oqlQuery).Execute()
Dim list As New List(Of Object)()
Dim i As Integer = 0
While i < Math.Min(maximumRows, data.Count)
list.Add(data(i + startRowIndex))
System.Math.Max(System.Threading.Interlocked.Increment(i), i - 1)
End While
Session("Count") = data.Count
Return list
End Function
Each filter expression (of type Telerik.Web.UI.GridFilterExpression)
has fieldName, fieldValue, columnUniqueName, dataTypeName and filterFunction
properties which hold the field name, field value (filter pattern typed by the user), the unique name
of the filtered column, the data type and the filter function applied to it (respectively). To retrieve
the values from these properties use the
get_fieldName(), get_fieldValue(),
get_columnUniqueName().get_dataTypeName()
and get_filterFunction()
properties of the corresponding GridFilterExpression. Below is a sample code excerpt using OnCommand
client-side event handler:
CopyASPX/ASCX
<telerik:RadGrid ID="RadGrid1" runat="server">
<ClientSettings>
<clientEvents OnCommand="RaiseCommand" />
</ClientSettings>
</telerik:RadGrid>CopyJavaScript
function RaiseCommand(sender, args) {
args.set_cancel(true);
var filterExpressions = sender.get_masterTableView().get_filterExpressions();
if (filterExpressions.length > 0) {
var expression = filterExpressions[0];
var fieldName = expression.get_fieldName();
var fieldValue = expression.get_fieldValue();
var columnUniqueName = expression.get_columnUniqueName();
var filterFunction = expression.get_filterFunction();
alert(expression.toString() + "/n" + expression.toDynamicLinq());
}
alert(filterExpressions.toString());
}
Where the possible values for the Telerik.Web.UI.GridFilterFunction
enumeration are listed below:
CopyJavaScript
Telerik.Web.UI.GridFilterFunction.prototype =
{
NoFilter : 0,
Contains : 1,
DoesNotContain : 2,
StartsWith : 3,
EndsWith : 4,
EqualTo : 5,
NotEqualTo : 6,
GreaterThan : 7,
LessThan : 8,
GreaterThanOrEqualTo : 9,
LessThanOrEqualTo : 10,
Between : 11,
NotBetween : 12,
IsEmpty : 13,
NotIsEmpty : 14,
IsNull : 15,
NotIsNull : 16,
Custom : 17
};
 Note |
|---|
The RadGrid get_filterExpressions() property is meaningful only in case the RadGrid control
is bound client-side.
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