Variables and HTML Forms

Currently I have the following script:-


function validate_form(){
if(regform.reguser.value == ""){
alert("Please completed the selected box");
regform.reguser.focus();
return false;
}else if(regform.regemail.value == ""){
alert("Please completed the selected box");
regform.regemail.focus();
return false;
}else if(regform.regpass1.value == ""){
alert("Please completed the selected box");
regform.regpass1.focus();
return false;
}else if(regform.regpass2.value == ""){
alert("Please completed the selected box");
regform.regpass2.focus();
return false;
}else{
return true;
}
}


to validate a simple registration form, however I initially tried to streamline this function by cycling through an array using a loop to point to various input elements in the HTML page itself. I found that when trying to use a variable in the aforementioned if statements the javascript failed to work i.e.


var test = "reguser";
if(regform.test.value = ""){
}


I know the javascript is looking for the input element "test" instead of "reguser" but is there any way I can force it to look for the contents of the variable.

regform.elements[test].value

var test = "reguser";
if(regform[test].value = ""){ ... }


EDIT: Oh, man! THREE minutes. I really am slowing down!