Validating Selection Lists

Selection lists are handled in the same way as other nontext objects using a for loop:

function windowreturn(field1){ 
myForm=document.forms[0];
 for (var i=0; i < myForm.field1.length; i++){
 if (myForm.list[i].selected) {
 choice = true;
 }
 }
self.close();
}

Here's an example using JavaScript to verify that no more than x number of options are selected in a selection list field:

choices = 0; 
for (var i=0; i < field1.length; i++){
 if (form.list[i].selected) {
 choices++;
 }
}
if (choices > 5) {
 alert("Sorry you can only pick 5 choices!");
} else {
 alert("You picked " + choices + " choices!");
}