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Server-side Programming Overview

Following is a table of the most important properties you should be aware of when working with RadClientDataSource.

General properties

Property	Description
AllowBatchOperations	Gets or sets a value indicating whether batch operations in the RadClientDataSource are enabled. Default is false . Serialized on the client-side to this kendo setting.
AllowPaging	Gets or sets value indicating whether paging is enabled or not. This is unique to the RadClientDataSource so it has not kendo counterpart!
EnableServerAggregates	Gets or sets value indicating whether server-side aggregates are enabled. Default is false .Serialized on the client-side to this kendo setting.
EnableServerFiltering	Gets or sets value indicating whether server-side filtering is enabled. Default is false .Serialized on the client-side to this kendo setting.
EnableServerSorting	Gets or sets value indicating whether server-side sorting is enabled. Default is false .Serialized on the client-side to this kendo setting.
EnableServerGrouping	Gets or sets value indicating whether server-side grouping is enabled. Default is false .Serialized on the client-side to this kendo setting.
EnableServerPaging	Gets or sets value indicating whether server-side paging is enabled. Default is false .Serialized on the client-side to this kendo setting.
PageSize	Gets or sets the maximum number of items that would appear on a page. Default is 10.Serialized on the client-side to this kendo setting.

This represents the client-side "transport" setting of the kendoDataSource and should allow the same type of server configuration to be serialized on theclient in the form of transport settings for the kendoDataSource.

WebServiceDataSourceSettings – holds all the transport settings for update/delete/insert operations. The following table represents the properties that WebServiceDataSourceSettings exposes.

Property	Description
BaseUrl	Serves to hold the common, repeating part of the Url of the CRUD operations which is then combined with their separate Url property.
BaseUrl	Serves to hold the common, repeating part of the Url of the CRUD operations which is then combined with their separate Url property.
ServiceType	Gets or sets a value indicating the type of service the DataSource is binding to. Enumeration with four values: Default , GeoJSON , OData and XML . Serialized on theclient-side to this kendo setting. Currently only OData v.2 is supported!
Select	Corresponds to the read setting in the kendoDataSource
Delete	Corresponds to the destroy setting in the kendoDataSource
Update	Corresponds to the update setting in the kendoDataSource
Insert	Corresponds to the create setting in the kendoDataSource

All of the above CRUD operations share the following common settings

Property	Description
Url	Holds the URL at which the request for the operation will be sent. If the BaseUrl propertyis specified – Url will hold only the distinct part specific to the operation. Corresponds to kendo url setting in the kendoDataSource.

ASPNET

<telerik:RadClientDataSource ID="RadClientDataSource1" runat="server">
    <DataSource>
        <WebServiceDataSourceSettings BaseUrl="http://myservice/">
            <Select Url="update" DataType="JSONP" />
        </WebServiceDataSourceSettings>
    </DataSource>
</telerik:RadClientDataSource>

| | DataType |Gets or sets the data type that is expected from the data service. Currently enumeration of three options: XML , JSON(default) , JSONP . Corresponds to kendo dataType setting in the kendoDataSource. | | EnableCaching |Enables or disables client-side data caching in RadClientDataSource . Caching is disabled by default.Corresponds to kendo cache setting in the kendoDataSource. | | ContentType |Gets or sets the content type that is expected from the data service. String value such as application/json .Corresponds to kendo contentType setting in the kendoDataSource. | | RequestType |Gets or sets the HTTP method that will be used to send the data to the service. The default is GET . Other possibleverbs are POST , PUT , DELETE . Corresponds to kendo type setting in the kendoDataSource. |

Schema

This represents the client-side "schema" setting of the kendoDataSource. It serves to provide metadata for the underlying types of objects returned from theservice. User can specify property names, their types and other configuration. The following table represents the properties that exposes.

Property	Description
ResponseType	Gets or sets the data type of the server response. Only XML and JSON (default) are supported.Serialized on the client-side to this kendo setting.
DataName	Gets or sets the name of the collection that holds the data items. Serialized on the client-side to this kendo setting.
AggregateResultsName	Gets or sets the name of the field from the response which contains the aggregate results. Serialized on the client-side to this kendo setting.
GroupsName	Gets or sets the name of the field from the server response which contains the groups. Serialized on the client-side to this kendo setting.
ErrorsName	Gets or sets the name of the field from the server response which contains server-side errors. Serialized on the client-side to this kendo setting.
TotalName	Gets or sets the name of the field from the server response which contains the total number of data items. Serialized on the client-side to this kendo setting.
Model	Gets or sets the model of the schema which holds the structure of the entity and various other settings.
Model-ID	Gets or sets the field serving as ID of the model. Necessary for CRUD operations.
Model-Fields	A collection of ClientDataSourceModelFields representing the settings for each field.Kendo equivalent here .Each ClientDataSourceModelField exposes the following properties.

FieldName - Gets or sets the name of the field from the model.
OriginalFieldName – Gets or sets the name of the orginal field from the data.
ParseFunctionName – Gets or sets the name of function which will parse the field value. If not set default parsers will be used.
Editable – Gets or sets field from the Model is editable. Default is true .
Nullable – Gets or sets field from the Model is nullable. Default is true .
DefaultValue – Gets or sets the default value of the field from the model.
DataType – Gets or sets the corresponding client-side type of the field from the model. Currently enumeration ( ClientDataSourceModelFieldType ) of 4 types: ( String , Number , Boolean , Data ).|

Expressions and aggregates

RadClientDataSource provides various API for controlling the different expressions that can be applied to the data such as filter, sort, group expressions and aggregates.

FilterExpression

FilterExpression - Hierarchical recursive structure that allows defining of nested complex filter expressions. Consists of two types derived from a common abstract base class:

Property	Description
ClientDataSourceFilterEntry	The main class that defines one filter entry with the following properties: ClientDataSourceFilterEntry and ClientDataSourceFilterExpression . The table below describes their properties.

FieldName - Gets or sets the field name for the operation. Kendo counterpart here.
Operator - Gets or sets the filtering operator. Lengthy enumeration containing the following values: EqualTo , NotEqualTo , GreaterThan , GreaterThanOrEqualTo , LessThan , LessThenOrEqualTo , Contains , EndsWith , StartsWith . Kendo counterpart here.
Value - Property containing the value on which to filter the data. The value is of type string .|

| ClientDataSourceFilterExpression |Special type of object that allows recursive nesting of the filter expressions. Has the following properties:

LogicOperator - Gets or sets the filter logic, AND or OR . Default is AND . Kendo counterpart here
Filters - A collection that can hold both ClientDataSourceFilterEntry and ClientDataSourceFilterExpression types. Allows unlimited nesting of filters. And the kendo counterpart here|

ASPNET

<telerik:RadClientDataSource ID="RadClientDataSource2" runat="server">
    <FilterExpression>
        <telerik:ClientDataSourceFilterExpression LogicOperator="Or">
            <telerik:ClientDataSourceFilterEntry FieldName="A" Operator="EqualTo" Value="1" />
            <telerik:ClientDataSourceFilterEntry FieldName="B" Operator="EqualTo" Value="2" />
        </telerik:ClientDataSourceFilterExpression>
        <telerik:ClientDataSourceFilterEntry FieldName="C" Operator="EqualTo" Value="3" />
    </FilterExpression>
</telerik:RadClientDataSource>

C#
var filter1 = new ClientDataSourceFilterExpression{ LogicOperator= ClientDataSourceFilterLogicOperator.Or};
filter1.Filters.Add(new ClientDataSourceFilterEntry { FieldName = "A", Operator = ClientDataSourceFilterOperator.EqualTo, Value = "1" });
filter1.Filters.Add(new ClientDataSourceFilterEntry { FieldName = "B", Operator = ClientDataSourceFilterOperator.EqualTo, Value = "2" });
RadClientDataSource1.FilterExpression.Filters.Add(filter1);
RadClientDataSource1.FilterExpression.Filters.Add(new ClientDataSourceFilterEntry { FieldName = "C", Operator = ClientDataSourceFilterOperator.EqualTo, Value = "3" });
VB.NET
Dim filter1 = New ClientDataSourceFilterExpression() With { _
Key .LogicOperator = ClientDataSourceFilterLogicOperator.[Or] _
}
filter1.Filters.Add(New ClientDataSourceFilterEntry() With { _
    Key .FieldName = "A", _
    Key .[Operator] = ClientDataSourceFilterOperator.EqualTo, _
    Key .Value = "1" _
})
filter1.Filters.Add(New ClientDataSourceFilterEntry() With { _
    Key .FieldName = "B", _
    Key .[Operator] = ClientDataSourceFilterOperator.EqualTo, _
    Key .Value = "2" _
})
RadClientDataSource1.FilterExpression.Filters.Add(filter1)
RadClientDataSource1.FilterExpression.Filters.Add(New ClientDataSourceFilterEntry() With { _
    Key .FieldName = "C", _
    Key .[Operator] = ClientDataSourceFilterOperator.EqualTo, _
    Key .Value = "3" _
})

The filter value on the server is always string (if the value property is not string it cannot be set through markup and thewhole filter expressions setting in the markup becomes useless). Consider the following filter expression:

ASPNET

<FilterExpression>
    <telerik:ClientDataSourceFilterEntry FieldName="Discontinued" Operator="EqualTo" Value="true" />
</FilterExpression>

By default this will filter the field Discontinued by the value "true" as string, but if the field is of other type (e.g. boolean) this will cause a client-side error from the kendoDataSource. To filter by other types different than string please specify the type of the field in the Schema settings of the control. This will make the RadClientSideDataSource try to parse the value as the specified type! (currently the parsing is done only client-side) Here is what settings are needed in order to filter the Discontinued field by Boolean value instead of string.

ASPNET

<Schema>
    <Model>
        <telerik:ClientDataSourceModelField FieldName="Discontinued" DataType="Boolean" />
    </Model>
</Schema>

The above is valid only for server-side settings. When you apply filter expressions through the client-side API no such issues exist because you set the value property to the same javascript value that you wish to filter on, and there’s no need to specify types in this case.

SortExpressions

SortExpressions - Gets a collection holding the ClientDataSourceSortExpression expressions of the data source. ClientDataSourceSortExpression is the main object of the collection defining one sort expression. Each group expressionprovides the following properties.

FieldName - Gets or sets the field name for the sort operation.
SortOrder - Gets or sets the sort order. Enumeration of three values: Asc, Desc and None. Default is None and the setting is not serialized tothe client.

ASPNET

	        <SortExpressions>
	            <telerik:ClientDataSourceSortExpression FieldName="ProductID" SortOrder="Asc"  />
	        </SortExpressions>

Aggregates

Aggregates – Gets a collection holding aggregates settings applied to the whole data of the dataSource. ClientDataSourceAggregate is the main object of the collection defining on aggregate. Each aggregate setting provides the following properties.

Field - Gets or sets the field name of the aggregate.
Aggregate - Gets or sets the aggregate function. An enumeration of the following values: Sum, Min, Max, Count, Average. Default is Sum.

ASPNET

	        <Aggregates>
	            <telerik:ClientDataSourceAggregate Aggregate="Sum" Field="UnitPrice" />
	        </Aggregates>

GroupExpressions

GroupExpressions - Get a collection holding the ClientDataSourceGroupExpression expressions of thedata source. ClientDataSourceGroupExpression is the main object of the collection defining one group expression. Each sort expressionprovides the following properties.

FieldName - Gets or sets the field name for the group operation.
SortOrder - Gets or sets the sort order. Enumeration of three values: Asc, Desc and None. Default is None and the setting is not serialized to theclient.
Aggregates - Get a collection of the aggregates settings applied to the current group.

ASPNET

<GroupExpressions>
    <telerik:ClientDataSourceGroupExpression FieldName="ProductName" SortOrder="Asc">
    </telerik:ClientDataSourceGroupExpression>
</GroupExpressions>

Server-side Programming Overview

General properties

DataSource settings

Schema

Expressions and aggregates