// Generic Form Validation

// Jacob Hage (jacob@hage.dk)

var checkObjects	= new Array();

var errors		= "";

var returnVal		= false;

var language		= new Array();

language["header"]	= "The following error(s) occured:"

language["start"]	= "-";

language["field"]	= " ";

language["require"]	= " is required";

language["min"]		= " and must consist of at least ";

language["max"]		= " and must not contain more than ";

language["minmax"]	= " and no more than ";

language["chars"]	= " characters";

language["num"]		= " and must contain a number";

language["email"]	= " must contain a valid e-mail address";

// -----------------------------------------------------------------------------

// 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;

   }

}