Question auto file name download?

[Dangerousboss]

I making program for downloading from YouTube to .mp4... User has to insert URL of video and my program download web source... find title,videoid, and T and make variable with download string... Then i use WebClient.DownloadFileAsync to download and i can download if I use :

Dim A as new WebClient
          A.DownloadFileAsync(downloadaddress,"C:\test.mp4")

I download like that... but i want one textbox with path where downloads being saved with auto file name (youtube video title)... when i try that it won't start download...

 

[cjard]

In that case.. just rename the file after it has finished downloading.. I can't quite see what the local file name has to do with the downloadability of a video though..

 

[Dangerousboss]

No.... I don't wanna rename it after dl.... i want to make textbox where would be path and one label with text : Title : (YouTube Video Name) .... And i want to webclient download from url to textbox2.text & label3.text & ".mp4"

BUt won't start !