QUESTION
Can anyone suggest how a loading image can be displayed until a gridview is fully loaded?
This gridview is to be rendered on page
As you are not willing to use the ASP.NET Update panel which is designed to handle the kind of requirement you have. Using jquery AJAX and using the web method to update the Grid will not work as you expect because you need to update the viewstate and other information. One of the solution that you can apply is showing the modal dialog box till your page is completed loaded its html which includes your Grid data.