How does angular2 (angular4) merge the same items in a table?

problem description

the environmental background of the problems and what methods you have tried

reference address: Baidu does not come out
wants to know how to design the merging of the same items above and below, how to implement the interface better, and the version of angular4.x adopted by the project

related codes

/ / Please paste the code text below (do not replace the code with pictures)

[
{"fileName":"111.pcap.00","startTime":"2018-06-05 10:16:04","taskName":"111","taskId":58,"fileId":72},
{"fileName":"111.pcap.01","startTime":"2018-06-05 10:16:55","taskName":"111","taskId":58,"fileId":73},
{"fileName":"aaa.pcap.00","startTime":"2018-06-05 10:10:28","taskName":"aaa","taskId":57,"fileId":71},
{"fileName":"www.pcap.00","startTime":"2018-06-05 10:50:28","taskName":"www","taskId":59,"fileId":79}
]

what result do you expect? What is the error message actually seen?

expect to merge the same items above and below. The left and right can introduce the algorithm