Develop Reference

Enable submit button only when no error is found

I have a simple application in which I only want to enable the calculate button only when no-errors are found (an error is recorded if the value is not a number, or a value is less than 0). I perform a few conditional checks using && and || operator. However, when only one input has been filled properly, without errors, the button is enabled. But, when an explicit wrong value has been specified the button is disabled again.
Code: https://github.com/KaustubhMaladkar/Tip-Calculator
if (!peopleError && !billError) {
submit.removeAttribute("disabled");
}
if (billError || peopleError) submit.setAttribute("disabled", "")
Live site: https://kaustubhmaladkar.github.io/Tip-Calculator/

I would like to thank that #Nestoro for their comments on my question as most, if not all, of my answer is based their comments.
This code will solve the problem
if (!peopleError && !billError && Number(billElem.value) && Number(peopleElem.value)) submit.removeAttribute("disabled");
else submit.setAttribute("disabled", "");

jQuery - Simple validation for two inputs

I have two inputs: the first one is X - file upload. the second one is Y- an input for an URL.
So far I have a code that checks if Y is valid then remove the attribute required for X. otherwise I want the X to be required.
$(Y).blur(function(){
if ($(this).is(':valid') == true) {
$(X).removeAttr('required')
} else if ($(this).is(':valid') == false) {
$(X).attr('required');
}
});
for some reason this code works when the input Y is valid it removes the attribute. But let's say the user regrets and wants to leave Y blank, it doesn't return the required attribute for X.
Tried to keep the explanation as simple and clear as possible. If there is a misunderstanding I'll try to edit this question and make it clearer.

The easiest way is:
$(Y).blur(function(){
if ($(this).is(':valid') == true && $(this).val() != '') {
$(X).removeAttr('required')
} else if ($(this).is(':valid') == false || $(this).val() == '') {
$(X).attr('required');
}
});
In that case when user removes the content, required attribute will be returned back (dont forget to add trim function, I didnt use it in the sample).
I would recommend to capsulate this logic into validation functions. I also dont like blur event (usability is bad), I would recommend onchange event for field validation.

Javascript validation of Adobe form (radio buttons)

I'm having difficulty (I'm new to JavaScript) figuring out a little validation in Adobe LiveCycle forms. I have a first choice (4 option) radio button, 2nd choice (same 4 options) and 3rd choice (same 4 options) where I'd like a validation to make sure the user doesn't enter the same result 3 times.
I thought it would be something like:
event.rc = true;
if ( form1.#subform[0].FirstChoice.rawValue != form1.#subform[0].SecondChoice.rawValue ! && form1.#subform[0].FirstChoice.rawValue != form1.#subform[0].ThirdChoice.rawValue !)
{
app.alert("You need three separate answers, you dimwit!");
event.rc = false;
}
Evidently, I am being a dimwit and going about this all wrong, but I've drawn a blank.
I was thinking also along the lines of:
form1.#subform[0].FirstChoice.rawValue <> form1.#subform[0].SecondChoice.rawValue ! && form1.#subform[0].FirstChoice.rawValue !<> form1.#subform[0].ThirdChoice.rawValue !)
but I don't know where to go with it.
Help (please), thanks.

You are pretty close. Try:
if ((Select1.rawValue != null && Select1.rawValue == Select2.rawValue) || (Select2.rawValue != null && Select2.rawValue == Select3.rawValue) || (Select3.rawValue != null && Select1.rawValue == Select3.rawValue))
{
app.alert("You need three separate answers, you dimwit!");
}
You need to cover the case where the Selections are not yet filled in. Select1, Select2, and Select3 are the RadioButton group.
I would put this as a calculation on a hidden field since you want it to recalculate whenever a change is made to the radio buttons.

javascript if condition && condition doesn't work

the AND && operator doesn't work, but when i replace it with an OR || operation it is workin, why? I just used OR || operator for testing, what i need is an && operator.
Please help. thanks
function validate() {
if ((document.form.option.value == 1) && (document.form.des.value == '')) {
alert("Please complete the form!");
return false
} else return true;
}
i also tried nested if but it doesn't work too
if(document.form.option.value==1)
{
if(document.form.des.value=='')
{
alert ("Please complete the form!");
return false
}
}

It sounds like || is what you are looking for here. The && operator is only true if both the left and right side of the && are true. In this case you appear to want to display the message if the value is 1 or empty. This is exactly what the || operator is for. It is true if either the left or right is true

If Or operator is working, means there are some javascript errors in your second part of condition. check document.form.des.value=='' (maybe just open your javascript console in Chrome/Firefox/IE8+)

its because one of the conditions specified above returns false and loop breaks. Is you use OR ,only one must be validated and returns true.. check your code for both the conditions.

Javascript only checks one field

Ok so I've been stumped on this one for days and its frustrating me. (Will frustrate me even more if it's something simple I'm overlooking).
I have a form generated in PHP which I want to verify that certain pieces are filled out. I do this via a JavaScript check when the user clicks the submit button.The JavaScript code is below:
<script language="JavaScript">
function checkFields()
{
if (document.getElementById('ldescription').value == '' || document.getElementById('uname').value == ''
|| document.getElementById('sdescription').value == '' || document.getElementById('email').value == ''
|| document.getElementById('platf').value == "Select Group" || document.getElementByID('cate').value == "Select Category" )
{
alert("Please fill out all of the starred (*) items" );
return false;
}
}
</script>
For some reason though this only checks the ldescription field. If that field has text but all the others are empty it carries on like everything was filled out. Also if I change the order of my checks and ldescription is anywhere but the first check, it will do no check whatsoever even when all the fields are empty.
Any ideas?
EDIT:
Got it fixed. Along with the suggestion I marked as correct the document.getElementById('item').value command worked with only textarea boxes but not regular text input boxes. By changing the command to document.MyForm.myTextName.value everything fell into place.

Couple of problems i noticed with your sample code.
The last getElementById call has improper casing. The final d is capitalized and it shouldn't be
Comparing the value to a string literal should be done by === not ==.
JSLint complains there are line break issues in your if statement by having the line begin with || instead of having the previous line end with ||.
The first and third items are most likely the ones causing your problem.

Inside your if condition, when you are breaking a line, make sure that the last token in the line is the OR operator ||.
Javascript does semicolon insertion, so it may be that semicolons are being inserted (automatically, invisibly, by the interpreter) in a bad place.
Try the below code
<script language="JavaScript">
function checkFields()
{
if (document.getElementById('ldescription').value === '' ||
document.getElementById('uname').value === '' ||
document.getElementById('sdescription').value === '' ||
document.getElementById('email').value === '' ||
document.getElementById('platf').value === "Select Group" ||
document.getElementById('cate').value === "Select Category")
{
alert("Please fill out all of the starred (*) items" );
return false;
}
}
</script>

Please use Javascript && operator which returns true if both the elements are true. || operator evaluates to true in case atleast one of the element is true which is what is happening in your case. You can take a look at Javascript boolean Logic