Select a select option element without a "selected" attribute - javascript

So here is the thing:
I have a java app and it creates a group of selects based on a db. Also, if it happens that an element (let's call it product) has that value, it print the option with the selected attribute.
<select>
<option value="1">text1</option>
<option value="2" selected>text2</option>
<option value="3">text3</option>
<option value="4">text4</option>
<option value="5">text5</option>
</select>
<select>
<option value="1">text1</option>
<option value="2">text2</option>
<option value="3">text3</option>
</select>
<select>
<option value="1">text1</option>
<option value="2">text2</option>
</select>
What i want to do is set in blank (set a value of zero) to the selects that not has an element with a selected value.
If you know another form to set to blank a list (diferent from put a default empty element in every select), please let me know.

The way to do this without an empty option, is to set the selectedIndex to -1
$('select:not(:has(option[selected]))').prop("selectedIndex", -1);
FIDDLE

Demo $('option:not(:selected)').val(0); use :not and :selected and set the value to 0

Related

Angular Dropdown menu does not show default value

With regular html select menus, if you create an option element with selected and disabled attributes and give that option text, then that text will display in the select menu by default. Here is basic html:
<select name="myname">
<option selected disabled>Select one...</option>
<option>Option 1</option>
<option>Option 2</option>
<option>Option 3</option>
</select>
This is what pages looks like:
But in the below isolated code, I demonstrate that Angular is intrusively not showing the option text:
https://github.com/lovefamilychildrenhappiness/DropDownNoShowDefaultValue
// app.component.html
<h1>Select Box does not show default value: </h1>
<app-select-box
[options]="collection"
></app-select-box>
// select-box.component.html
<select
[value]="value"
[disabled]="disabled">
<option selected disabled value="">Select one...</option>
<option *ngFor="let option of options">{{option}}</option>
</select>
What is causing Angular to disrupt the native html behavior of select boxes?
This is because your select value is bound to a variable called value which is undefined initially. As per the html, there is no option with a value of undefined, so nothing gets selected. Your Select one... option has an empty string value. So to fix this, initialize value in your component to an empty string.
value: string = '';
just put the option to be selected in the first place.
<option value="0">value to be selected<option>
<option value="1">next<option>
<option value="2">Continues<option>

bootstrap-select not selecting the correct item

I am using bootstrap select Bootstrap-select v1.7.2 in Angular. When I select some option from drop down it selects some other option.
Plunker is setup here:
http://plnkr.co/edit/MRYOkW?p=preview
(code is in dashboard.html and dashboard.js)
That's how I am creating it. bootstrap-dropdown is the directive that initiates the drop-down.
<select ng-model="vm.CurrCustomer.Logic" name="ddlLogic" bootstrap-dropdown >
<option>Contains</option>
<option>Greater Than</option>
<option>Less Than</option>
<option>Equal To</option>
</select>
You missed to add value attribute on your options that would set value of ng-model on select of any option
<select ng-model="vm.CurrCustomer.Logic" name="ddlLogic" bootstrap-dropdown>
<option value="">Contains</option>
<option value="Greater">Greater Than</option>
<option value="Less">Less Than</option>
<option value="Equal">Equal To</option>
</select>
Update
If you want to render select option dynamically I'd refer you to use ng-options which support select perfectly. You can select object on selection of option
Demo here
problem is you can't add option value property . either set value property or generate this using ng-repeat option
Above answer must be the right answer but, It seems like you had an unwanted empty option an it was messing the index. By adding a real one it started to work.
<select ng-model="vm.CurrCustomer.Logic" name="ddlLogic" bootstrap-dropdown >
<option></option>
<option>Contains</option>
<option>Greater Than</option>
<option>Less Than</option>
<option>Equal To</option>
</select>

jquery :selected always picks first element if none are selected

I have a select element
<select id='bill_to'>
<option value='a634jhj2'>test#c.com</option>
<option value='agfd4ghj2'>test2#c.com</option>
<option value='asdf634jhj2'>tes3#c.com</option>
<option value='agf2342d4ghj2'>test4#c.com</option>
</select>
If I do
$('#bill_to').find(':selected')
it returns the first option even though it is not selected.
If an option is selected
$('#bill_to').find(':selected')
works as expected and returns the correct option
What am I doing wrong? Is this a bug. This is driving me crazy.
I just want it to return [] if there is nothing selected
If there are no select option with selected attribute, first option will be the selected option by default. You can try adding another option to top that contains default value as follow.
<select id='bill_to'>
<option value='-1'>Select<option>
<option value='a634jhj2'>test#c.com<option>
<option value='agfd4ghj2'>test2#c.com<option>
<option value='asdf634jhj2'>tes3#c.com<option>
<option value='agf2342d4ghj2'>test4#c.com<option>
</select>
If nothing is selected you will get -1 and then you can proceed.
e.g. http://jsfiddle.net/fZv5t/
I have add closing tag of option "", without this I am having an empty option get inserted after each option in the dropdown. Issue can be seen in this Fiddle.
And the working example is on this Fiddle.
Try to add an empty option tag:
<select id='bill_to'>
<option></option>
<option value='a634jhj2'>test#c.com</option>
<option value='agfd4ghj2'>test2#c.com</option>
<option value='asdf634jhj2'>tes3#c.com</option>
<option value='agf2342d4ghj2'>test4#c.com</option>
</select>
Here you will get empty string, like this:
$('#bill_to').find(':selected').val();
If you can't or don't want to add a dummy first <option>, as an alternative you can grab and test the selected attribute of the element returned by :selected, for example:
var selection = $('#bill_to').find(':selected');
var really = (selection.attr('selected') != null);
var selval = really ? selection.val() : ""; /* or null or whatever */

Select a <select> <option> based on it's value containing a string

<select id='mySelect'>
<option value='FirstOption'>
Option 1
</option>
<option value='SecondOption'>
Option 2
</option>
</select>
I'd like to select the 2nd option based on the fact it has the word 'Second' in it's name.
What I've Tried
$('#mySelect').val('SecondOption');
Closest I've got. Obviously returns second option, but wouldn't work for 'AnotherSecondOption'
Try * attribute-contains-selector
$('#mySelect option[value*="Second"]').prop('selected',true);

Can I apply the required attribute to <select> fields in HTML?

How can I check if a user has selected something from a <select> field in HTML?
I see <select> doesn't support the new required attribute... do I have to use JavaScript then? Or is there something I’m missing? :/
Mandatory: Have the first value empty - required works on empty values
Prerequisites: correct html5 DOCTYPE and a named input field
<select name="somename" required>
<option value="">Please select</option>
<option value="one">One</option>
</select>
As per the documentation (the listing and bold is mine)
The required attribute is a boolean
attribute.
When specified, the user
will be required to select a value
before submitting the form.
If a select element
has a required attribute specified,
does not have a multiple attribute specified,
and has a display size of 1 (do not have SIZE=2 or more - omit it if not needed);
and if the value
of the first option element in the
select element's list of options (if
any) is the empty string (i.e. present as value=""),
and that
option element's parent node is the
select element (and not an optgroup
element),
then that option is the
select element's placeholder label
option.
The <select> element does support the required attribute, as per the spec:
http://dev.w3.org/html5/spec-author-view/the-select-element.html#the-select-element
Which browser doesn’t honour this?
(Of course, you have to validate on the server anyway, as you can’t guarantee that users will have JavaScript enabled.)
Yes, it's working:
<select name="somename" required>
<option value="">Please select</option>
<option value="one">One</option>
</select>
you have to keep first option blank.
You can use the selected attribute for the option element to select a choice by default. You can use the required attribute for the select element to ensure that the user selects something.
In Javascript, you can check the selectedIndex property to get the index of the selected option, or you can check the value property to get the value of the selected option.
According to the HTML5 spec, selectedIndex "returns the index of the first selected item, if any, or −1 if there is no selected item. And value "returns the value of the first selected item, if any, or the empty string if there is no selected item." So if selectedIndex = -1, then you know they haven't selected anything.
<button type="button" onclick="displaySelection()">What did I pick?</button>
<script>
function displaySelection()
{
var mySelect = document.getElementById("someSelectElement");
var mySelection = mySelect.selectedIndex;
alert(mySelection);
}
</script>
You need to set the value attribute of option to the empty string:
<select name="status" required>
<option selected disabled value="">what's your status?</option>
<option value="code">coding</option>
<option value="sleep">sleeping</option>
</select>
select will return the value of the selected option to the server when the user presses submit on the form. An empty value is the same as an empty text input -> raising the required message.
w3schools
The value attribute specifies the value to be sent to a server when a form is submitted.
Example
<form action="">
<select required>
<option selected disabled value="">choose</option>
<option value="red">red</option>
<option value="yellow">yellow</option>
<option value="green">green</option>
<option value="grey">grey</option>
</select>
<input type="submit">
</form>
try this, this gonna work, I have tried this and this works.
<!DOCTYPE html>
<html>
<body>
<form action="#">
<select required>
<option value="">None</option>
<option value="volvo">Volvo</option>
<option value="saab">Saab</option>
<option value="mercedes">Mercedes</option>
<option value="audi">Audi</option>
</select>
<input type="submit">
</form>
</body>
</html>
Make the value of first item of selection box to blank.
So when every you post the FORM you get blank value and using this way you would know that user hasn't selected anything from dropdown.
<select name="user_role" required>
<option value="">-Select-</option>
<option value="User">User</option>
<option value="Admin">Admin</option>
</select>
first you have to assign blank value in first option.
i.e. Select here.than only required will work.
Works perfectly fine if the first option's value is null. Explanation : The HTML5 will read a null value on button submit. If not null (value attribute), the selected value is assumed not to be null hence the validation would have worked i.e by checking if there's been data in the option tag. Therefore it will not produce the validation method. However, i guess the other side becomes clear, if the value attribute is set to null ie (value = "" ), HTML5 will detect an empty value on the first or rather the default selected option thus giving out the validation message. Thanks for asking. Happy to help. Glad to know if i did.
In html5 you can do using the full expression:
<select required="required">
I don't know why the short expression doesn't work, but try this one.
It will solve.
Try this
<select>
<option value="" style="display:none">Please select</option>
<option value="one">One</option>
</select>
You can do it also dynamically with JQuery
Set required
$("#select1").attr('required', 'required');
Remove required
$("#select1").removeAttr('required');

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