I want to take the time of polyline

I am drawing polyline with czml.
Click on polyline to get relative time and epoch.
(I want to display the time)
Please tell me how.

Cesium version:1.57
browser:chrome

You should be able to use scene.pick on a mouse click handler to get the object under the mouse, and then you can do something like polyline.position.getValue(viewer.clock.currentTime) to get its position or value at a current time. You can see a picking example here:

https://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=Picking.html

Thank you for your reply!
I can not get polyline. .
Please teach me

Can you post a complete Sandcastle example (https://cesiumjs.org/Cesium/Apps/Sandcastle/index.html) of your code so I can try it out? You can click “share” and paste the link here.