Advice Required

[Chris]

I have a handheld device running Windows CE 4.2 that I need to send and
receive information from/to our Informix database using WiFi

I have a few development tools I can use to help me do this, VB6, eVB and
VB.Net 2005 (I have little experience in this though but it is my preferred
tool, it would be a nice learning project). I have Compact Framework 2.0
SP1. I can get simple VB.Net apps running on the device

I have tried in .Net using Compact Framework to connect directly to the
Informix database, but I have been unable to do so. Is this possible?

Since I have been unable to do this I have looked at other options.

1) I thought about using Web Services but I can't seem to find any decent
information or samples for VB.Net 2005 to achieve this. Is there a good site
out there I haven't found? I can't seem to connect my web service to my
database.

2) I also thought about using a Winsock type control to connect to a PC
which controls all of the connectivity to the Informix database, but again I
can't find a lot of information about how to do this.

Can anyone point me in the right direction on how to achieve connectivity to
my Informix database.

I don't really want to use eVB and the Winsock control in that. I'm not a
fan of eVB and it's limitations.

Many thanks for any help or assistance provided


Chris

 

[Jon Vaughan]

Hi Chris,

I have used webservices as an interface to interacting with a database. In
vs 2003 its as simple as adding a reference to your webservice in
webreferences, note : dont use localhost , use the machine name or ip
address , scuh as http://TestServer/AppName/Service.

Example calling the web service ( in c# )

WebServiceEngine.Products objWebservice;

objWebservice = new WebServiceEngine.Products();

dsProducts = objWebservice.GetAllProducts();

HTH

 

[David D Webb]

Web services are a good way to go. .NETCF 2.0 has some improved stuff, and
there are some libraries in OpenNetCF as well. The only issue is that they
are a bit high level, so its difficult to trace connectivity issues
sometimes.

Web services will be friendly for any DMZ's and the server-side services can
handle the business logic, access restictions, and shield the handheld app
from any data layer changes. Its generally not a good idea to directly
connect to the database. You don't want to have to distribute a new app
everytime the data model changes - its easy to update server services
though.

Use SQL Mobile on the handheld for storing local copies of the data. If you
design the app correctly, you can have it work in a disconnected mode which
is always good - there is no such thing as an always-connected device.

-Dave