Downloading Files from Web Server

[Bill Norris]

I've been using the following code to download one file from web server. The value of FileUrl is set with the appropriate file I am downloading. Is possible to send a list of files to download, or is necessary to do them individually, by changing the value of FileUrl for each file.

Sub get_new_data
   HttpUtils.CallbackActivity = "Main" 'Current activity name.
    HttpUtils.CallbackJobDoneSub = "JobDone"
    HttpUtils.Download("Job1", FileUrl)
End Sub
   
Sub JobDone (Job As String)
   If HttpUtils.IsSuccess(FileUrl) Then 
File.Copy2(HttpUtils.GetInputStream(FileUrl),File.OpenOutput(File.DirDefaultExternal,"filename",False))
   End If
End Sub

 

[admac231]

The second example here shows how to download a list.

 

[Zeev Goldstein]

urgent help needed...

:sign0085::sign0085:
hi,
i'm trying to download a text file from a website using the above sample
the result is an empty file
what i get is the file in the right place but no content - it is empty

i'm using this exact sample, just changed the file name and url, naturally

alternatively - can any one help with a good & simple example on how to directly download a text file from a url ?

this is really urgent for me and i do appreciate any help

thanks

 

[Bill Norris]

RE:

try inserting this line after the file.copy2 line

httputils.GetInputStream.close

I had a similar problem when I first started with this but Erel got me on the right track.

 

[Erel]

Closing the input stream will not help. You should close (or flush) the output stream.

 

[Zeev Goldstein]

oh god, oh silly me...
i solved it myself by just reading what i have done
thank you all for at least trying
thanks

 

[Zeev Goldstein]

Erel & Bill - thanks for your input - that was very helpful.

 

[Zeev Goldstein]

another question - if i may...

guys,

since you've been so kind & helpful, i have another question if i may:

how do i trap the back key so it wont exit the app but i will be able to show a message or page or anything ekse ?

secondly how do i trap errors ?
in vb.net i have try or vb6 there is on error - what is the procedure in b4a ?

thanks alot...

 

[lagore]

To catch the back key

Sub Activity_KeyPress (KeyCode As Int) As Boolean  ' Return true to consume the event
   If KeyCode = KeyCodes.KEYCODE_BACK  Then  ' Back button
        'your code here
      Return True  ' Consume event, so the app does not close
   Else
       Return False ' Do not consume, the app will close or go to previous activity
   End If
End Sub

For error catching (from the B4A HelpViewer which is indispensable)

Exception
Holds a thrown exception.
You can access the last thrown exception by calling LastException.
For example:
Try
   Dim in As InputStream
   in = File.OpenInput(File.DirInternal, "SomeMissingFile.txt")
   '...
Catch
   Log(LastException.Message)
End Try
If in.IsInitialized Then in.Close

 

[Zeev Goldstein]

OMG - guys you are all saints
you are saving me a lot of time and effort drilling down forums and web sites
this is priceless!!
thanks once again

 

[Zeev Goldstein]

ok - now it the real hard nut...

guys - a real hard nut for you -

anyone has any info on how to use a printer ?
i mean - i have a samsung bixolon spp-200 - it's a thermal printer with bluetooth card reader.
anyone has any experience with such a nut ?

thansk