Hello,

This is the expected behaviour - __doPostBack is a built-in ASP.NET function that posts the whole page back. I believe what you are looking for is called invokeXmlHttpRequest and is documented here:

http://help.infragistics.com/Help/NetAdvantage/NET/2008.3/CLR3.5/html/WebGrid_Object_CSOM.html

invokeXmlHttpRequest

Forces xmlHttpRequest to be fired to the server in LoadOnDemand=Xml mode.

Number. The type of the out-of-band callback to execute. Has to be an integer. See UltraWebGrid.eRegType enumeration for recognizable values.

Object. If the request type deals with an object it needs to be passed here (ChildRows requires a row object etc). This parameter is not used for all types of requests. The object is expected to be different for different types of requests:

eReqType.UpdateCell - the cell that is being updated;

eReqType.AddNewRow - the rows collection a new row is added to;

eReqType.Sort - the rows collection that is being sorted;

eReqType.ChildRows - the row which child rows are requested;

eReqType.DeleteRow - the row that is being deleted;

eReqType.UpdateRow - the row that is being updated.

eReqType.Filter - the rows collection the filter is being applied to;

eReqType.FilterDropDownFill - the rows collection the filter is being applied to;

eReqType.Refresh - optional; if nothing passed in the top rows collection is assumed. Otherwise either rows collection or a row is expected. When rows collection is passed in this collection is refreshed; when a row is passed in its child rows are refreshed.

No type restriction. Converted to string. If any data is required for the request it needs to be passed here.

eReqType.UpdateCell - new cell's value;

eReqType.Filter - the column object the filter is being applied to;

eReqType.FilterDropDownFill - the column object the filter is being applied to;

eReqType.Custom - any custom data defined by the developer.

Example: If oGrid is the grid object a possible use of the method would be:

oGrid.invokeXmlHttpRequest(oGrid.eReqType.Custom,null,
  "my data here");