c# - How to implement file downloader to detect communication breakage? -


i need implement file downloader in c#. downloader running on client computer, , download several files according several conditions.

the main restriction have client go offline during downloading (sometime more once), need following things happen:

1) downloader should notice there isn’t network communication anymore , pause downloading.

2) downloader should resume downloading once communication back, , continue collecting packages, adding them downloaded local disk.

i have checked stackoverflow previous posts , saw there 2 options – webclient , webrequest (using 1 of inheritance classes). wondering if can advise 1 use based on requirements have specified. how can detect communication breakage?

you need system.net.httpwebrequest send http requests , system.io.filestream access files. 2 methods needed httpwebrequest.addrange , filestream.seek

httpwebrequest.addrange method adds byte range header request, , range parameter specifies starting point of range. server start sending data range parameter specified end of data in http entity. while filestream.seek method used access current position within stream.

source , example


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