How to set the first select option to always be blank

Question

I am using angularjs in a project and in which I am using ng-options for generating <select>.

Initially, when the pages reload and no option element is selected, the HTML generated like below:

<select size="3" ng-model="item" ng-options="s.name for s in itemlist">
<option value="?" selected="selected"></option>
<option value="0">Item 1</option>
<option value="1">Item 2</option>
<option value="2">Item 3</option>
</select>

But when I select an element (ex. Item 2) the first blank select is gone. I know its happening as ng-model is being set by select value. But I want first select always blank so that user can reset the filter.

Psychedelic

Answer 1

This will do the work for you:

<select size="3" ng-model="item" ng-options="s.name for s in itemlist">
    <option value="">Select Option</option>
</select>

Gillead

My hero! I've been struggling with ng-options for quite a while now having the exact same problem as @Psychedelic had. This is the only permanent and solid solution. Thank you! – Armin

onChange directive is not firing if you select this option. – Long

This doesn't work while using the select box as a filter criteria. As when you want to reset the filter, on choosing 'Select Option', it doesn't reset the results. – Anhanhalt

Answer 2

For anyone out there that treat "null" as valid value for one of the options (so imagine that "null" is a value of one of the items in typeOptions in example below), I found that simplest way to make sure that automatically added option is hidden is to use ng-if.

<select ng-options="option.value as option.name for option in typeOptions">
    <option value="" ng-if="false"></option>
</select>

Why ng-if and not ng-hide? Because you want css selectors that would target first option inside above select to target "real" option, not the one that's hidden. It gets useful when you're using protractor for e2e testing and (for whatever reason) you use by.css() to target select options.

Kevin - Sưu Tầm

Arequipa

Answer 3

You can forgo using the ng-options and use ng-repeat instead and make the first option blank. See example below.

<select size="3" ng-model="item">
    <option value="?" selected="selected"></option>
    <option ng-repeat="s in itemlist" value="{{s.value}}">{{s.name}}</option>
</select>

Sectary

ng-options is the 'angular way' for select elements and (once used correctly) adds a lot of facility that ng-repeat doesn't. – Matty

@Matty : Straight from the AngularJS documentation: "In many cases, ngRepeat can be used on <option> elements instead of ngOptions to achieve a similar result." docs.angularjs.org/api/ng/directive/select – Sectary

@Sectary The same link also states (it might have been updated since you initially posted it, though) that ng-options is more efficient - faster and uses less memory, because it doesn't create a new scope for each item in the list. – Cymogene

I know this is old but, it is a valid solution for some scenarios, regardless of the micro-performance optimizations for your page, and doesn't deserve the down vote. The inclusion in the documentation is nod toward that fact and there are still some niche cases where ng-repeat on a select is just more straight forward. – Aronson

Answer 4

It appears that your best option would be to have the blank item included as the first item in itemlist.

Handkerchief

that creates two blank select when dom initialize. – Psychedelic

Answer 5

The solution above will corrupt the model with junk data. Please use the directive to reset the model in the right way JS: Select Option

Directive"
 .directive('dropDown', function($filter) {
    return {

        require: 'ngModel',
        priority: 100,
        link: function(scope, element, attr, ngModel) {

            function parse(value) {

                if (value) {

                    if(value === "")
                    {
                        return "crap"
                    }
                    else
                    {
                        return value;
                    }

                } else {
                    return;
                }
            }


            ngModel.$parsers.push(parse);

        }
    };
});

Fester

Answer 6

I had same problem and after a lot of googling,I understood the main issue was related to my angular version, if you use Angular 1.6.x, just use the ng-value directive and it will work as expected.

also I set an initial value in my controller, like this :

$scope.item = 0;

Winfrid

Answer 7

        <select ng-model="dataItem.platform_id"
            ng-options="item.id as item.value for item in platformList"
            ng-init="dataItem.platform_id=dataItem.platform_id||platformList[0].id"></select>

Mediaeval

Answer 8

Controller

$scope.item = '';

$scope.itemlist = {
   '' = '',
   'Item 0' = 1,
   'Item 1' = 2,
   'Item 2' = 3
};

HTML

<select data-ng-model="item" data-ng-options="v as k for (k, v) in itemlist"></select>

Nephology