The taskResizeHandling property (string) specifies how the onTaskResize event will be handled by the JavaScript Gantt Chart component.
"Disabled" - task box resizing is not allowed
"Update" - updates the task box position on the client side
"PostBack" - fires the server-side TaskMove event using PostBack (ASP.NET WebForms)
"CallBack" - fires the server-side TaskMove event using CallBack (ASP.NET WebForms, ASP.NET MVC, Java)
"JavaScript" - api=1, fires the onTaskResize event handler (ASP.NET WebForms, ASP.NET MVC, Java)
"Update"Gantt Chart config:
{
taskResizeHandling: "Disabled",
// ...
}