URLDownloadToFile question *resolved*

[kleinma]

I am using URLDownloadToFile in an auto update application i am writing for my main application.

I got everything working, but is there anyway I can cancel a download that has been started using that API call? If I simply terminate the exe, the file still continues to download.

I want to give the user the ability to click a cancel button to opt out of downloading if they need to for some reason.

I am using Edanmo's olelib.tlb file so that I could impliment the IBindStatusCallback interface to make a progress bar and all that... it works fine.. I just need to be able to cancel it.

The API guide says this about the function

· lpfnCB
Address of the caller's IBindStatusCallback interface. URLDownloadToFile calls this interface's IBindStatusCallback::OnProgress method on a connection activity, including the arrival of data. IBindStatusCallback::OnDataAvailable is never called. Implementing IBindStatusCallback::OnProgress allows a caller to implement a user interface or other progress monitoring functionality. It also allows the download operation to be canceled by returning E_ABORT from the IBindStatusCallback::OnProgress call. This can be set to NULL.

but I am unsure of how to return E_ABORT from the OnProgress call, as it is a sub and not a function (at least in Edanmo's olelib.tlb implimentation it is)

[kleinma]

solved it....

but for anyone who is interested....

I dimmed an object (objBind) of type IBinding

in the IBindStatusCallback_OnStartBinding call I set the object to pib (which is passed into this method)

I also set it to nothing in the IBindStatusCallback_OnStopBinding method.

I was then able to create a sub and call it from my form

Sub AbortDownload()
    If Not objBind Is Nothing Then
        objBind.Abort
    End If
End Sub

[Wokawidget]

There is not a thread on VBF that covers this topic correctly
Many people use the URLDownloadToFiLe API, but it seems that no-one knows what to pass in for the lpfnCB param of this API.
My form implements IBindStatusCallback but the progress sub doesn't fire. This I know if due to be not passing the correct param into the URLDownloadToFile API...

Any ideas...?

Woof

[kleinma]

it does now doesn't it

[Wokawidget]

No
Was working till silly o'clock last night.
Had a few hrs sleep.
had a dream about a dog getting squished my a lorry, very gory Woke up and decided to come to work and smash my computer...hahahaha.

*yawn*

Stupid code *sulk*

Gonna start from scratch and write it line by line and see if I can get it to work.

Woof

[DiGiTalErRoR]

I just coded my own winsock downloader.... Complete control!

[Wokawidget]

Don't suppose you could post the code...?

Woof

[jhermiz]

Originally posted by DiGiTalErRoR
I just coded my own winsock downloader.... Complete control!

dig what happened to all your posts ?

[Wokawidget]

hahahaha...68...NOOB!

Not gonna take any advice from you now.



awooooooo awooooooo HONK HONK!

[jhermiz]

Originally posted by Wokawidget
hahahaha...68...NOOB!

Not gonna take any advice from you now.



awooooooo awooooooo HONK HONK!

he used to be in the thousands...

UPDATE Posts SET PostCount=0 WHERE UserName= 'DiGiTalErRoR'

Edit: Damn hax0r username.

[MikkyThomeon]

For simplicity, I would also like to know how to get the URLDownloadToFile function to report progress and be able to cancel the operation. If sombody could please post some code about how to do this successfully, I would be rally grateful. It seems that there is little documentation about how to do this...

TIA
Mike

PS: Please see my related post: http://www.vbforums.com/showthread.p...hreadid=295984


[UPDATE] OK I have searched the forums and the links to mvps... are not working. Also the links to the edanmo type library are not working out OK...

[MikkyThomeon]

Hi Me again

http://www.mvps.org/emorcillo

[Wokawidget]

I have got it working.
And boy does it work perfectly

However, I emailed the code to myself from work, but it hasn't appeared
Not happy as I was gonna do some alterations.

I am at work tmrw. The code will be posted here in under 14 hrs Sorry about this.

It's actually dead easy to do, and I have no idea why there isn't much documentation on the web about it

There is however one thing I have found wrong with it. If you want your app to silently download soemthing from the web then it only works if you do not have a download manager installed on your PC, like DAP. If you do then this launches and takes over your download!!! This is VERY VERY annoying and I can't seem to stop it, apart from uninstalling the download manager. Booooooooooooooo


Woof

[alexandros]

in my humble opinion it is time to use .NET for this type of internet programming

[Wokawidget]

I have to agree with you here, but alas, when someone knows VB6 VERY well, and their entire app is in VB6, and they do not have .NET then other solutions must be found. Fact of development.

Anyways, the link to the tlb files is:

http://www.mvps.org/emorcillo/vb6/tlb/olelib.shtml

Download the zip, and copy the tlb files to your System32 folder and register them. Instructions are on the page.

These tlb files allow you to create callback functions.

Now, download my the zip, and run it.
There isn't much coding involved and the general VB stuff is quite basic. It helps if you know how call backs work, but this isn't important as you can still modify the code without this knowledge.

This example has the preset source of the AllAPI's APIGuide. This is what it downloads. The file is about 2.5Mb.

It's dead annoying while testing as you have to keep deleting the file from the temp internet files folder other wise the download takes about 0 seconds

If you need any help give me a shout.

Regards,

Woof

[MikkyThomeon]

Have to agree with you about .NET!!!!!!

The project I have been working on involves knowing almost everything about the most common internet protocols around just to get the thing working. And then dealing with network events.... My app is extensively event driven and it is a nightmare putting all the modules together!!!

[Wokawidget]

Did you get the code working?

Woof

[kleinma]

Originally posted by Wokawidget


It's dead annoying while testing as you have to keep deleting the file from the temp internet files folder other wise the download takes about 0 seconds

Woof

that is why you write a kill line in your code to kill the temp internet file each time

[Wokawidget]

I KILL the destination file, but when I try to KILL the file in Temp Internet files it says file not found because it's under a hidden folder in windows

Boooooooooooooooooooooooooooooooo

[kleinma]

you can show hidden files, or even then it still does't let you call kill on it because its marked as hidden?

[Wokawidget]

It's the Local folder under "Documents and Settings\Wokawidget" that is hidden. The Temp Internmet files folder is in this.

I could unhide it I suppose.

Woof

[MikkyThomeon]

Hi Woka

I have been pulled off that and am working hell for leather to get an random encrytion decryption / privat key scheme working.

Hanv not forgotten!!! Will be ready for more stuff after Friday. Thanks for your response. You are always attentive when someone has a problem and I do appreciate that fact!!! On the weekend I will have more time and be able to tackle the issue...

[MikkyThomeon]

No this method sux because of files being cached locally. It is alseo a bit too much of a heavyweight implementation for my app and is somewhat of an overkill. I will stick to the winsock method where I have complete control and no freezing etc.

[MikkyThomeon]

No this method sux because of files being cached locally. It is alseo a bit too much of a heavyweight implementation for my app and is somewhat of an overkill. I will stick to the winsock method where I have complete control and no freezing etc.

[MikkyThomeon]

http://www.vbforums.com/showthread.p...nsock+download

Apparently you can set a different flag in the URLDownloadToFile call and that will force the newer version to be downloaded.