Hi,
I have produced websites which launch windows forms. You can't launch a process already installed on a local machine but you can launch it using the .Net ClickOnce deployment mechanism.
ClickOnce application are just like any .Net windows application except they can be deployed onto a webserver and as the name suggests installed and launched with a single click.
You need to work through a few examples. The first shows you how to create a ClickOnce deployment for your application.
Deploying Windows Forms Applications with ClickOnce[
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If you need the form to be aware of state information from the users current ASP.Net session it is possible to use the querystring to pass values into the application.
How to: Retrieve Query String Information in an Online ClickOnce Application[
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The downside is, with this being a Microsoft product it only works seamlessly with IE. Although it can be enabled for Chrome and Firefox via the following:
ClickOnce for Google Chrome[
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Microsoft .Net Framework Assistant for Firefox[
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