using a loop as an alternative

[westmich]

I found a tutorial on using the 'confirm()' method of JavaScript. I made some modifications to use it a form validation. Currently, it's a series of repeated if statements. I know it could be simplified with a loop, but I'm not sure on how to do it.

<script language=javascript type="text/javascript">
<!--
function verify(){
		 if (document.forms[0].firstName.value == "") {
	   	    alert("You must enter a first name!");
		    document.forms[0].firstName.focus();
			return false;
		 }
		 if (document.forms[0].lastName.value == "") {
	   	    alert("You must enter a last name!");
		    document.forms[0].lastName.focus();
			return false;
		 }
		 if (document.forms[0].address.value == "") {
	   	    alert("You must enter an address!");
		    document.forms[0].address.focus();
			return false;
		 }
		 if (document.forms[0].city.value == "") {
	   	    alert("You must enter a city!");
		    document.forms[0].city.focus();
			return false;
		 }
		 if (document.forms[0].state.value == "") {
	   	    alert("You must enter a state!");
		    document.forms[0].state.focus();
			return false;
		 }
		 if (document.forms[0].zip.value == "") {
	   	    alert("You must enter a zip code!");
		    document.forms[0].zip.focus();
			return false;
		 }else{
		    msg = "Is This Information Correct? \n\n First Name: " + document.forms[0].firstName.value + "\n Last Name: " + document.forms[0].lastName.value + "\n Address: " + document.forms[0].address.value + "\n City: " + document.forms[0].city.value + "\n State: " + document.forms[0].state.value + "\n Zip Code: " + document.forms[0].zip.value + "\n\n";
            return confirm(msg);
		 }
}
// -->
</script>


<form action="http://localhost/testWeb/" method="post" onSubmit="return verify()">
<table border=0>
<tr>
       <td>First Name:&nbsp;</td>
       <td><input type=text name="firstName" size=12></input></td>
</tr>
<tr>
       <td>Last Name:</td>
       <td><input type=text name="lastName" size=12></input></td>
</tr>
<tr>
       <td>Address:</td>
       <td><input type=text name="address" size=15></input></td>
</tr>
<tr>
       <td>City:</td>
       <td><input type=text name="city" size=15></input></td>
</tr>
<tr>
       <td>State:</td>
       <td><input type=text name="state" size=2></input></td>
</tr>
<tr>
	   <td>Zip Code:</td>
	   <td><input type=text name="zip" size=5></input></td>
</tr>
<tr>
	   <td colspan=4 align="center"><input type=submit value="Submit"></input>
	   <input type=reset value="Reset"></input></td>
</tr>
</table>
</form>

Also, a loop would allow me to add or subtract fields in the form.

Feel free to copy and paste this code for your own use