If you already have dashboard of refresh start & end Timestamp then you just need to export data from Dashboard.
Just go into worksheet where you have displayed those data and select "Worksheet" from top of the window.
worksheet --> Export--> Data
Thanks for the reply.
Actually, dashboard has all the datasources refreshed recently. But the refresh start time and end time will be seen only when we hover on that data source. It is a tool tip.
What i need is,timestamps of all data sources refreshed in last 3 hours and to be exported into an excel.
Why don't you create one view like
Dashboard name, Start refresh time, End refresh time instead of using those information in tooltip.
Then export data into excel as I told you in earlier post.