I am currently writing an utility that takes two different sets of data from an excel document and sends it to two different web services. Each set of data has it’s own button that sends the data to the web service. When the a button is clicked, the corresponding web service then returns data depending on the input values.
What I am trying to do is so that this utility can be distrobuted and used by a wide variety of people. What they are going to do is they are going to be synchronizing there particular cells of their own excel document to the corresponding cell in my utility. Using simple excel formulas. For example:
c:\temp\[book1.xls]sheet1'!a1
Now what I am trying to do is automatically “click” the button, or update, on my utility when the user links their cell to its corresponding cell on my utility.
I have tried the selection change event on my page. But it doesn’t actually process until my utility is active, or clicked on.
Is there a way to make my utility automatically update? It would be especially awesome if somehow it did this while my utility was closed. So when the user opens it it is already filled with their information, and the outputs are correct.
The requirements:
you need to guarantee that when a user is using excel your app can collect the data. Your app may not be running at the time. You need the Worksheet_SelectionChange() event to fire automatically not just when your app is active.
Solution:
Basically in order to guarantee that the Worksheet_SelectionChange() is running all the time, and in order to guarantee that whenever the user opens an instance of excel you are able to collect and process the data/formulas entered into the particular target range address you need to wire up the selectionchange event inside of a VB.NET Excel COM Addin. There are several ways to do this, but since your using VB.NET your best off using the newest approach which is building a VSTO COM Addin.
There are numerous other questons available on how to best build a VSTO addin (some in C# some in VB.NET but all this information is exactly the same for both, just different syntax).
So you will need two projects. Your existing one, plus a Excel VSTO addin (which you can also do in VB.NET).
Now inside the selectionchange event you should make sure that your code handles the target range correctly; ie. make sure you check for non-contigious groups of ranges with a selection… A1:B1;D2:E2 and copy the data to your app. You may consider using a format such as xml to serialise the latest data from excel so that if your app is not open at the time, it can deserialise and read back the data stored for it the next time it is opened. I guess it really depends how your handling the data (i.e. is it for loading into a datagrid?) and whether you are going to do further processing and store it somewhere else later (in which case maybe you can put it straight into a database from the addin in excel).