Validating an email address with more than one domain name and eliminating the rest

[SIPRNet11]

I would like to validate an email address using more than one specific domain name.  My current code (which I found here) for validating an email address with one specific domain name is:

(function (){
var sDomain = "mail.mil";
if(!event.value) return;
var sEnteredDomain = event.value.split("@")[1];
if (typeof sEnteredDomain === "undefined" || sEnteredDomain.toLowerCase() !== sDomain){
event.rc = false;
app.alert("Your email address must end with:  " + sDomain, 3);
}
})();

FYI: I am using this code in a PDF form.

[try67 · Accepted solution]

Try this:

(function (){ 
var sDomains = ["mail.mil", "mail.gov", "mail.org"]; 
if(!event.value) return; 
var sEnteredDomain = event.value.split("@")[1]; 
if (typeof sEnteredDomain === "undefined" || sDomains.indexOf(sEnteredDomain.toLowerCase())==-1 ){ 
event.rc = false; 
app.alert("Your email address must end with one of the following domains:  " + sDomains.join("\n"), 3); 
} 
})();

[SIPRNet11]

Duh!  So you set it up like an array, is that correct?  What does the -1 do in line 5?

Thank you sir!

[try67]

Yes, I converted the sDomain string to an array, renamed it, and adjusted the rest of the code to work with it.

Regarding the -1, read this: JavaScript Array indexOf() Method