Is it possible to freeze some row from D&D? That means, when D&D, checked rowId first, if it is special one, it will be locked and not let to be D&D.
There is no such functionality , you can set onDrag handler to filter d-n-d, in such case any row can be dragged, but only allowed row can be droped ( not exactly the desired behaviour )
There is no public event, but you can manually inject code in dhtmlGrid_drag.js , function _createDragNode, for example next line
dhtmlXGridObject.prototype._createDragNode=function(htmlObject,e){
if (!this.callEvent(“onBeforeDrag”,[htmlObject.parentNode.idd])) return null;
This will introduce new grid event - onBeforeDrag, which will be called before d-n-d, and returning false from which will block d-n-d operation.