In case you wonder how Expression Web deals with custom ASP.NET controls, there are 2 things to notice :
- Having the control assembly into the \bin directory will not give you any design time rendering in Expression Web.
- Expression Web do not support custom controls into the Toolbox.
Ok, that's not good so far...
So how do you get custom controls to work in Expression Web ?
Andrew Jewsbury, the Expression Web program manager gives a solution on his blog :
Basically you have to install the custom control in the GAC, then use a "<%@ Register Assembly=..." tag with fully qualified name, or a "<add assembly=..." tag in the <controls> section of your web.config.
Humm, this is not a designer friendly solution... but it works.
Note only the "<%@ Register Assembly=..." seems to work for me.
Then you get full design time support and even smart tag as well as IntelliSense in code for your customs controls.