Grid / Declarative Binding

This example demonstrates how to use declarative client-side data-binding.

RadGrid declarative client-side data-binding is very similar to ObjectDataSource data-binding. You need to specify SelectMethod and SelectCountMethod (if needed) along with Location property and the grid will automatically invoke the specified method as PageMethod or WebService method:

...
<ClientSettings>
    <DataBinding Location="~/Grid/Examples/Client/DeclarativeDataBinding/WebService.asmx"
        SelectMethod="GetData" SelectCountMethod="GetCount" />
</ClientSettings>
...

Important: These methods should be marked with WebMethod attribute! Example:

    [WebMethod(EnableSession=true)]
    public List<MyBusinessObject> GetData(int startRowIndex, int maximumRows, List<GridSortExpression> sortExpression, List<GridFilterExpression> filterExpression)
    {
        ...
    }

In the ClientSettings.DataBinding section you can also specify the following properties:

• StartRowIndexParameterName - default is "startRowIndex"
• MaximumRowsIndexParameterName - default is "maximumRows"
• SortParameterName - default is "sortExpression"
• FilterParameterName - default is "filterExpression"

Important: By default RadGrid will expect SelectMethod with four arguments with the following names and types:

• int startRowIndex
• int maximumRows
• List<GridSortExpression> sortExpression
• List<GridFilterExpression> filterExpression

and SelectCountMethod with no arguments!

To change values on the fly of any of the grid declarative client-side data-binding properties you can use the OnDataBinding client-side event:

...
<ClientEvents OnDataBinding="RadGrid1_DataBinding" />
...

Please refer to the JavaScript code in this demo for more info.

To optimize even more the grid client-side data binding you can get both data and total items count in a single request. Example:

...
    [WebMethod(EnableSession = true)]
    public Dictionary<string, object> GetDataAndCount(int startRowIndex, int maximumRows, List<GridSortExpression> sortExpression, List<GridFilterExpression> filterExpression)
    {
        Dictionary<string, object> data = new Dictionary<string, object>();

        data.Add("Data", GetData(startRowIndex, maximumRows, sortExpression, filterExpression));
        data.Add("Count", (int)Session["Count"]);

        return data;
    }
...

The grid will check automatically for "data" and "count" and will not execute a second request!