What is the best way to redirect a domain to another url in MVC C# using a wildcard

Question

I have a domain1 which is now sharing IP address with an other domain2. I have a rewrite config where I can list the rewrites individually however there are 90 urls for domain1. I would like to do this in a more efficient way by creating a wildcard. Is the syntax below correct to say redirect domain including all pages?

For example:

<add key="http://domain1.com/*" value="https://domain2.com/"/>

Or would it be better done in IIS?

<rule name="redirect domain sharing IP address" stopProcessing="true">
  <match url=".*" ignoreCase="true" />
   <conditions>
     <add input="{HTTP_HOST}" pattern="^(www.)?domain1.com" />
   </conditions>
  <action type="Redirect" url="domain2.com/test" redirectType="Permanent" />
</rule>

Answer 1

Why get tricky or obscure? A simple

string myUrl = "http://www.domain1.com/whatever/...";
const string newDomain = "www.domain2.com";
const string oldDomain = "www.domain1.com";

myUrl = myUrl.Replace(oldDomain,newDomain);

Should do the trick to "translate" the incoming url