<!-- FIVE STEPS TO INSTALL EXTERNAL JS:
/*
  1.  Copy the first code in a new file, save it as validation.js
  2.  Include the .js file in the HEAD of your HTML document
  3.  Define the validation rules for each field in the HEAD section
  4.  Insert the onLoad event handler into your BODY tag
  5.  Add validate() to your submit button, as shown below -->

*/
<!-- STEP ONE: Paste this code into a new file, save as validation.js  -->


// Generic Form Validation
// Jacob Hage (jacob@hage.dk)
var checkObjects	= new Array();
var errors		= "";
var returnVal		= false;
var language		= new Array();
language["header"]	= "Os seguintes erro(s) ocurreram:"
language["start"]	= "->";
language["field"]	= " Campo ";
language["require"]	= " e necessario";
language["min"]		= " e deve conter pelo menos ";
language["max"]		= " e não deve conter mais de ";
language["minmax"]	= " e não mais de ";
language["chars"]	= " characteres";
language["num"]		= " e deve conter um numero";
language["email"]	= " deve conter um enderço e-mail valido";
// -----------------------------------------------------------------------------
// define - Call this function in the beginning of the page. I.e. onLoad.
// n = name of the input field (Required)
// type= string, num, email (Required)
// min = the value must have at least [min] characters (Optional)
// max = the value must have maximum [max] characters (Optional)
// d = (Optional)
// -----------------------------------------------------------------------------
function define(n, type, HTMLname, min, max, d) {
var p;
var i;
var x;
if (!d) d = document;
if ((p=n.indexOf("?"))>0&&parent.frames.length) {
d = parent.frames[n.substring(p+1)].document;
n = n.substring(0,p);
}
if (!(x = d[n]) && d.all) x = d.all[n];
for (i = 0; !x && i < d.forms.length; i++) {
x = d.forms[i][n];
}
for (i = 0; !x && d.layers && i < d.layers.length; i++) {
x = define(n, type, HTMLname, min, max, d.layers[i].document);
return x;       
}
eval("V_"+n+" = new formResult(x, type, HTMLname, min, max);");
checkObjects[eval(checkObjects.length)] = eval("V_"+n);
}
function formResult(form, type, HTMLname, min, max) {
this.form = form;
this.type = type;
this.HTMLname = HTMLname;
this.min  = min;
this.max  = max;
}
function validate() {
if (checkObjects.length > 0) {
errorObject = "";
for (i = 0; i < checkObjects.length; i++) {
validateObject = new Object();
validateObject.form = checkObjects[i].form;
validateObject.HTMLname = checkObjects[i].HTMLname;
validateObject.val = checkObjects[i].form.value;
validateObject.len = checkObjects[i].form.value.length;
validateObject.min = checkObjects[i].min;
validateObject.max = checkObjects[i].max;
validateObject.type = checkObjects[i].type;
if (validateObject.type == "num" || validateObject.type == "string") {
if ((validateObject.type == "num" && validateObject.len <= 0) || (validateObject.type == "num" && isNaN(validateObject.val))) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + language['num'] + "\n";
} else if (validateObject.min && validateObject.max && (validateObject.len < validateObject.min || validateObject.len > validateObject.max)) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + language['min'] + validateObject.min + language['minmax'] + validateObject.max+language['chars'] + "\n";
} else if (validateObject.min && !validateObject.max && (validateObject.len < validateObject.min)) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + language['min'] + validateObject.min + language['chars'] + "\n";
} else if (validateObject.max && !validateObject.min &&(validateObject.len > validateObject.max)) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + language['max'] + validateObject.max + language['chars'] + "\n";
} else if (!validateObject.min && !validateObject.max && validateObject.len <= 0) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + "\n";
   }
} else if(validateObject.type == "email") {
// Checking existense of "@" and ".". 
// Length of must >= 5 and the "." must 
// not directly precede or follow the "@"
if ((validateObject.val.indexOf("@") == -1) || (validateObject.val.charAt(0) == ".") || (validateObject.val.charAt(0) == "@") || (validateObject.len < 6) || (validateObject.val.indexOf(".") == -1) || (validateObject.val.charAt(validateObject.val.indexOf("@")+1) == ".") || (validateObject.val.charAt(validateObject.val.indexOf("@")-1) == ".")) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['email'] + "\n"; }
      }
   }
}
if (errors) {
alert(language["header"].concat("\n" + errors));
errors = "";
returnVal = false;
} else {
returnVal = true;
   }
}