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asp.netiiscassini

Differences in behaviour between IIS and the ASP.Net Web Development Server?

During development, I usually test ASP.Net applications using the Web Development Server (sometimes called Cassini). Occasionally, when I publish to a real IIS environment, I notice that the application behaves differently.

So, what are the differences between the way that production IIS servers and the ASP.Net Web Development Server behave? I don't mean differences in feature sets (clearly IIS has lots of features that are not present in WDS), but differences in the way they handle ASP.Net.

BTW: There are a few differences noted in the responses to this question, but I am sure there must be more.

Solution

  • Some differences might be:

    • You can't use virtual directories while working with cassini. This might lead to unexpected behaviour when deploying for the first time, due to missing folder permissions. (e.g. You have a /image/ directory on your local machine, but in the IIS /image/ is the virtual directory pointing elsehwere)
    • Some third party assemblies (like ComponenArt Web DLL) cause problems with specific port issues. It's best to develop with the IIS to minimize compability problems on deploying.
    • The trustlevel of the target IIS might be lower that your development settings, this might result in malfunctioning, depending on what you do with the IIS, like reading the Uptime.