Combine IF and SWITCH to apply SNAT based on destination IP and/or TCP port

So in this case if a connection hits my L4 VS/Irule with a destination of 10.10.10.10 and tcp port 104 will I get the first SNAT from within the IF statement, or will it continue to match and apply the second SNAT from withing the SWITCH statement?

2nd SNAT - 10.10.70.70

You can try using some kind of "return" statement if you want to stop processing after 1st match or you can change the order of matching depending on your requirements.

If you want the port to take precedence, you can use it above the IP address check. For example: 10.10.10.10:104 - which SNAT do you want to use ?

Both of the statements would run. The return would end processing at that point.

If you want the switch statement to run, but not if the IP address matches 10.10.10.10, why not add an if statement to your switch statement? There are probably more elegant ways to accomplish this:

 if destination IP is 10.10.10.10 SNAT to .15 regardless of TCP port
when CLIENT_ACCEPTED {if { [IP::addr [IP::local_addr] equals 10.10.10.10/32] } 
{log local0. "Export Server [IP::client_addr] sending outbound connection to [IP::local_addr]:[TCP::local_port], applying SNAT 10.10.70.15"
snat 10.10.70.15 }

 if tcp port matches anything in the switch list use .70 snat
switch [TCP::local_port] {
"104" -
"4000" -
"12000" -
"7400" {
    if {[IP::addr [IP::local_addr] not 10.10.10.10/32] }{
        snat 10.10.70.70
        log local0. “Host with IP address [IP::client_addr] sending outbound connection to [IP::remote_addr]:[TCP::local_port], applying SNAT 10.10.70.70”
    }
}
 otherwise don't do anything...
default {
}
}
}

when CLIENT_ACCEPTED {
  if { [IP::addr [IP::local_addr] equals 10.10.10.10/32] } {
    switch [TCP::local_port] {
      "104" -
      "4000" -
      "7400" -
      "12000" { snat 10.10.70.70 }
      default { snat 10.10.70.15 }
    }
  }
}

At this point, though, you're getting close to wanting to use a datagroup instead of switch.