IIS Rewrite Module and sub applications

Here's what I have deployed:

testRedirect is an empty website. All sub-applications are sub-folders that have been converted in application. All of them are ASP .Net MVC sites.

Here's what I want to setup:

Http://localhost/ must show the content of SiteName1 without displaying Http://localhost/SiteName1/ in the adress bar (it must stay Http://localhost/)
Http://localhost/SiteName1/ must show the content of SiteName1 without displaying Http://localhost/SiteName1/ in the adress bar (it must stay Http://localhost/)
Http://localhost/SiteName2/ shows the content of SiteName2 and displays Http://localhost/SiteName2/ in the adress bar (Same behavior for SiteName3 & SiteName4 and any other sites....)

In other words, I want my SiteName1 to act like a home site

What I've tried so far, is something similar to the answer provided by @cheesemacfly here:

<rules>
    <rule name="Redirect if SiteName1" stopProcessing="true">
        <match url="^SiteName1/(.*)$" />
        <action type="Redirect" url="{R:1}" />
    </rule>
    <rule name="Rewrite to sub folder">
        <match url="^.*$" />
        <action type="Rewrite" url="SiteName1/{R:0}" />
    </rule>
</rules>

It works great for Case1 & 2 but not the other ones.

I tried to add rules like this one, but it was not successful...

<rule name="if_not_SiteName1" stopProcessing="true">
   <match url="^SiteName1/(.*)$" negate="true" />
   <action type="None" />
</rule>

I think your best option would be to trigger the rewrite rule you already have only when the url doesn't start with one of your sub-applications.

It would be something like:

<rules>
    <rule name="Redirect if SiteName1" stopProcessing="true">
        <match url="^SiteName1/(.*)$" />
        <action type="Redirect" url="{R:1}" />
    </rule>
    <rule name="Rewrite to sub folder">
        <match url="^(SiteName2|SiteName3|SiteName4)/" negate="true" />
        <action type="Rewrite" url="SiteName1/{R:0}" />
    </rule>
</rules>

We keep the redirect when SiteName1/ is requested (we don't need to change this), but the rewrite rule is triggered only when the requested url doesn't start with SiteName2/ or SiteName3/ or SiteName4/ (that's what url="^(SiteName2|SiteName3|SiteName4)/" means and we use negate="true" to triggered the rule only when the pattern is not matched).