There are times when you want to store the value that was passed along in an event in the profile. Let's consider this example, where an event is published when the visitor hits the play button of a video player and the title of the video is passed along as event context:
window.blueConicClient.event.publish('play_button_clicked',['my Homevideo']);
If you want to store this context value in the profile, use the following JavaScript expression in the "JavaScript expression" expression field:
eventContext[0]