The OnLoadJS field on the EntityUI record allows us to define the customized OnLoad javascripts to a form. However in some senarios, we may want to pass the OnLoad javascript in the parameter of the form url to make the form behave differently based on different OnLoadJS values in the parameter. For example, when rendering a new Task form for collection the feedback or issues submitted from customer, we want to simplify the Task form by only showing the subject and content. To achieve this, we passed OnLoadJS=OnlyShowContent() in the parameter of the query string so the form will call OnlyShowContent after loaded and hide all unwanted form fields. The whole url will look like this http://www.primeobjects.com/form.aspx?ename=Task&OnLoadJS=OnlyShowContent().
Note: The OnlyShowContent function need to be defined in a javascript file used by the Task entity.