jQuery detect if textarea is empty
I am trying to determine if a textarea is empty if a user deletes what is already pre-populated in the textarea using jQuery.
Anyway to do this?
This is what I have and its not working
$(textarea).live('change', funct开发者_运维问答ion(){
if($(this).val().length == 0) {
$(submitButtonClass).addClass('disabled_button');
$(submitButtonClass).removeClass('transSubmit');
} else {
$('.disabled_button').addClass('transSubmit').css({
'cursor':'pointer'
}).removeClass('disabled_button');
}
});
if (!$("#myTextArea").val()) {
// textarea is empty
}
You can also use $.trim
to make sure the element doesn't contain only white-space:
if (!$.trim($("#myTextArea").val())) {
// textarea is empty or contains only white-space
}
if (!$.trim($("element").val())) {
}
I know you are long past getting a solution. So, this is for others that come along to see how other people are solving the same common problem-- like me.
The examples in the question and answers indicates the use of jQuery and I am using the .change listener/handler/whatever to see if my textarea changes. This should take care of manual text changes, automated text changes, etc. to trigger the
//pseudocode
$(document).ready(function () {
$('#textarea').change(function () {
if ($.trim($('#textarea').val()).length < 1) {
$('#output').html('Someway your box is being reported as empty... sadness.');
} else {
$('#output').html('Your users managed to put something in the box!');
//No guarantee it isn't mindless gibberish, sorry.
}
});
});
Seems to work on all the browsers I use. http://jsfiddle.net/Q3LW6/. Message shows when textarea loses focus.
Newer, more thorough example: https://jsfiddle.net/BradChesney79/tjj6338a/
Uses and reports .change(), .blur(), .keydown(), .keyup(), .mousedown(), .mouseup(), .click(), mouseleave(), and .setInterval().
To find out if the textarea is empty we have a look at the textarea text content and if there is one sinlge character to be found it is not empty.
Try:
if ($(#textareaid).get(0).textContent.length == 0){
// action
}
//or
if (document.getElmentById(textareaid).textContent.length == 0){
// action
}
$(#textareaid)
gets us the textarea jQuery object.
$(#textareaid).get(0)
gets us the dom node.
We could also use document.getElmentById(textareaid)
without the use of jQuery.
.textContent
gets us the textContent of that dom element.
With .length
we can see if there are any characters present.
So the textarea is empty in case that there are no characters inside.
You just need to get the value of the texbox and see if it has anything in it:
if (!$(`#textareaid`).val().length)
{
//do stuff
}
Here is my working code
function emptyTextAreaCheck(textarea, submitButtonClass) {
if(!submitButtonClass)
submitButtonClass = ".transSubmit";
if($(textarea).val() == '') {
$(submitButtonClass).addClass('disabled_button');
$(submitButtonClass).removeClass('transSubmit');
}
$(textarea).live('focus keydown keyup', function(){
if($(this).val().length == 0) {
$(submitButtonClass).addClass('disabled_button');
$(submitButtonClass).removeClass('transSubmit');
} else {
$('.disabled_button').addClass('transSubmit').css({
'cursor':'pointer'
}).removeClass('disabled_button');
}
});
}
if(!$('element').val()) {
// code
}
This will check for empty textarea as well as will not allow only Spaces in textarea coz that looks empty too.
var txt_msg = $("textarea").val();
if (txt_msg.replace(/^\s+|\s+$/g, "").length == 0 || txt_msg=="") {
return false;
}
Andy E's answer helped me get the correct way to working for me:
$.each(["input[type=text][value=]", "textarea"], function (index, element) {
if (!$(element).val() || !$(element).text()) {
$(element).css("background-color", "rgba(255,227,3, 0.2)");
}
});
This !$(element).val()
did not catch an empty textarea for me. but that whole bang (!) thing did work when combined with text.
$.each(["input[type=text][value=]", "textarea[value=]"], function (index, element) {
//only empty input and textarea will come here
});
You can simply try this and it should work in most cases, feel free to correct me if I am wrong :
function hereLies(obj) {
if(obj.val() != "") {
//Do this here
}
}
Where obj
is the object of your textarea
.
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<html>
<body>
<textarea placeholder="Insert text here..." rows="5" cols="12"></textarea>
<button id="checkerx">Check</button>
<p>Value is not null!</p>
<script>
$("p").hide();
$("#checkerx").click(function(){
if($("textarea").val() != ""){
$("p").show();
}
else{
$("p").replaceWith("<p>Value is null!</p>");
}
});
</script>
</body></html>
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