I am trying to validate an html form using javascript the code is bellow
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title></title>
</head>
<body>
<script type="text/javascript">
function validate(){
if(document.form1.thbox.checked)
{
alert("yes");
}
else
alert("no");
}
</script>
<form name="form1" method="get">
<input type="checkbox" name="thebox"/>
<input type="button" value="press me" onclick="validate()"/>
</form>
</body>
</html>
when ever I try to press on button nothing works
Can someone please tell me why is that?
Thank you
Change if(document.form1.thbox.checked) to if(document.form1.thebox.checked) You have missed e in thebox
http://jsfiddle.net/eJhzf/
Perhaps because checked is not a valid property of undefined:
HTML:
name="thebox"
Javascript:
form1.thbox.checked
Notice the missing e, so, it should be:
form1.thebox.checked
use this method
if ( document.form1.thebox.checked == false )
{
alert ( "Please select check box." );
}
else {
// your code or message
}
and use thebox instead of thbox
Related
I know there are 2-3 similar questions are on site but the mine is very specific.
So the situation is, I created a input field that validates a string if it matches /abc/ pattern (regex in javascript). But the output is very unexpected i.e., Even If i provide a input that matches the pattern then output is "Invalid input" and if i provide a input that doesn't matches the pattern then same above output. This is okay but I am unable to figure out what is what is happening when I am providing a valid input?
Here is the code:
<!DOCTYPE html>
<html>
<head>
<title>form validation</title>
</head>
<body>
<script>
function check() {
var field = document.getElementById("1").data;
var regex = /abc/;
if(regex.test(field) === true)
document.getElementById("2").innerHTML="Input accepted";
else
document.getElementById("2").innerHTML="Invalid input!";
}
</script>
First field:<br />
<input type="text" id="1"> <span id="2"></span> <br />
<button type="submit" onclick="check();">Validate</button>
</body>
</html>
document.getElementById("1").data
Is not a valid method. You have to use value method to obtain the data inside the input box. Try this code:
<!DOCTYPE html>
<html>
<head>
<title>form validation</title>
</head>
<body>
<script>
function check() {
var field = document.getElementById("1").value;
var regex = /abc/;
if(regex.test(field) === true)
document.getElementById("2").innerHTML="Input accepted";
else
document.getElementById("2").innerHTML="Invalid input!";
}
</script>
First field:<br />
<input type="text" id="1"> <span id="2"></span> <br />
<button type="submit" onclick="check();">Validate</button>
</body>
</html>
PS: Please do use a bit of debugging tools that the browsers provide.
try using .value instead of .data
<script>
function check() {
var field = document.getElementById("1").value; //<--- here
var regex = /abc/;
if(regex.test(field) === true)
document.getElementById("2").innerHTML="Input accepted";
else
document.getElementById("2").innerHTML="Invalid input!";
}
</script>
Now if you write "abc" its will works.
This question already has an answer here:
Javascript not working on submit
(1 answer)
Closed 5 years ago.
I recently started doing form validation and I am trying to understand something. I have yet to find this anywhere else on SE.
When I have onsubmit="return validateForm()" or onsubmit="validateForm()" in the <form> element, the form does not do anything. However, when I remove onsbumit from the form tag and instead do document.forms["favorite"].onsubmit = function validateForm() in the JS file, it works fine.
I got it working, but I am trying to understand why the "normal" method of onsubmit in the html isn't working.
For reference, here is my code as it works now:
HTML:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script type="text/javascript" src="form.js"></script>
<title>Form</title>
</head>
<body>
<form name="favorite" action="#" method="post">
Favorite Car Brand: <input type="text" name="car">
<input type="submit" value="Submit">
</form>
</body>
</html>
JS:
window.onload = function(){
document.forms["favorite"].onsubmit = function validateForm(){
var input = document.forms["favorite"]["car"].value;
if(input == ""){
alert("You missed an entry");
return false;
}
}
}
First of all we define a function and then we call that function. and you are calling that function before defining as you are using window.load.You need to define the validation function before window.load as you are using. Sorry for my poor English.
<script>
window.onload = function () {
function validateForm() {
var input = document.forms["favorite"]["car"].value;
if (input == "") {
alert("You missed an entry");
return false;
}
}
}
</script>
define validateForm() function before window.load you do not need to write this function inside the window.load.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Form</title>
<script>
function validateForm() {
var input = document.forms["favorite"]["car"].value;
if (input == "") {
alert("You missed an entry");
return false;
}
}
</script>
</head>
<body>
<form name="favorite" action="#" onsubmit="return validateForm();" method="post">
Favorite Car Brand: <input type="text" name="car">
<input type="submit" value="Submit">
</form>
</body>
</html>
I'm trying to get a search box that when it takes an input it sends the user to a specific page. But for some reason that, I cannot figure out, it doesn't do anything when an input is given. My code is the following:
<!DOCTYPE html>
<html>
<head>
<title>TEST</title>
<script type="text/javascript">
var input = document.getElementById("search");
function sendToPage(){
if (input.value == "happy"){
location.href="suggestion_happy.html";
}
else if (input.value == "sad"){
location.href="suggestion_sad.html";
}
else {
alert('Invalid Input.');
}
}
</script>
</head>
<body>
<div>
<form onsubmit="sendToPage()">
<input type="text" method="put" id="search" placeholder="Search" value="">
</form>
</div>
</body>
</html>
Please help I'm still kind of new to javascript :)
you don't need to create a form to do this
check out this code
<!DOCTYPE html>
<html>
<head>
<title>TEST</title>
<script type="text/javascript">
function sendToPage(){
var input = document.getElementById("search").value;
//alert(input);
if (input == "happy"){
location.href = "suggestion_happy.html";
return false;
}
else if (input == "sad"){
location.href = "suggestion_sad.html";
return false;
}
else {
alert('Invalid Input.');
}
}
</script>
</head>
<body>
<div>
<input type="text" method="put" id="search" placeholder="Search" value="">
<input type='submit' onclick="sendToPage();" />
</div>
</body>
</html>
<script type="text/javascript">
function sendToPage(){
var input = document.getElementById("search").value;
//alert(input);
if (input == "happy"){
//location.href="suggestion_happy.html";
location.replace("suggestion_happy.html");
return false;
}
else if (input == "sad"){
location.replace("suggestion_sad.html");
return false;
}
else {
alert('Invalid Input.');
}
}
</script>
<div>
<form action="" onsubmit="return sendToPage()" method="post">
<input type="text" id="search" placeholder="Search" value="">
</form>
</div>
I have edited my asnwer plz try this
there are two problems here:
submitting a form will always refresh the page. So onsubmit is
killing your app
by putting the js in the <head> your
document.getElementById call fails because that element doesn't
exist yet. Javascript belongs at the end of the page, just before
the closing </body> tag
I have written the below mentioned javascript and have called on the button click event but somehow it doesn't work, please someone help.
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
</head>
<script type="text/javascript">
function f1()
{
var x=document.getElementById("txt1").innerHTML
if(x==1)
{
alert("hello");
}
}
</script>
<body>
<form id="form1">
<input type="text" id="txt1"/><br/>
<input type="button" id="btn1" value="submit" onclick="f1()"/>
</form>
</body>
</html>
You're trying to grab innerHTML from an input field when you should be grabbing the value otherwise it'll always be undefined:
Change:
var x = document.getElementById("txt1").innerHTML;
to:
var x = document.getElementById("txt1").value;
JSFiddle Example
http://jsfiddle.net/moogs/dNWNP/1/
It should not be .innerHTML, but .value.
You should use value instead of innerHTML:
var x=document.getElementById("txt1").value;
See the jsfiddle.
I really don't know why this validation doesn't work.
this is my html:
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script type='text/javascript' src="scripts.js"></script>
<title>Test Page!</title>
</head>
<body>
<form onsubmit ="return validateFormOnSubmit(this)" name="myForm" action = "testForm.html">
<input name="textField" type="text" value="" size="50" id= "textfield" /> <br />
<input name="button" type="submit" value="Submit"/>
</form>
</body>
</html>
and this is my javascript file:
function isURL(fld){
var error = "";
var regex = /(ftp|http|https):\/\/(\w+:{0,1}\w*#)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%#!\-\/]))?/
if(regex.test(fld.value)){
error = "No URL's Allowed!";
}
else{
error = "";
}
return error;
}
function validateFormOnSubmit(myForm) {
var reason = "";
reason += isURL(myForm.textField);
if (reason != "") {
alert("there's something wrong: \n" + reason);
return false;
}
return true;
}
Thanks for your help.
update: is the action really required? testpage.html is just an empty html file here!
update 2: The problem is I don't see any message or alert.
It works fine, your scripts.js file isn't loaded properly or an old version is cached in your browser
Looks like you're passing in the form, rather than the field that you're trying to validate.