hello,

i am using this snippet it works fine 

https://www.aspsnippets.com/Articles/ASPNet-AJAX-Timer-control-Tutorial-with-example.aspx

i need to have a logic , i have 2 fields in database

start date time: 17/sep/2018  8:00 

end date time : 17/sep/2018 8 :15

current date time continuos changin: 17/sep/2018 8:10

differnce between 15 minute

i want when a page load it shows to user in running timer that how minutes left from current datetime minus to end date time

so in above example above it shows 5 minutes left and timer keeps on running till 0 please advice