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Query: “Is it possible to use both 'DataSource' field inEjsGridtag and also use 'WebApiAdaptor' inEjsDataManager?”
No. It is not possible to bind DataSource property and EjsDataManager simultaneously to same Grid. You can use either DataSource property or EjsDataManager to use WebAPI Adaptor. While use DataSource property, CRUD operation will take place locally. So it will be reflected only in local data. Similarly while using WebAPI Adaptor, PUT, POST,DELETE request will be sent to server and changes will be saved in your database directly.
But if you use both DataSource property and EjsDataManager to same Grid, DataSource property is considered and CRUD operations are handled locally. We suggest you to use either DataSource property or EjsDataManager for Grid. Please let us know the details about why you want to use both DataSource property and EjsDataManager for same Grid, it will be helpful for us to analyze about your requirement and update you the solution as early as possible.