Change the value of an attribute in an angular directive

Question

I've got a requirement such that for certain type of scope variables, I want to keep two decimal places in AngularJs. For this I've done the following:

html

<span floatval="{{someVariable}}">{{someVariable}}</span>

js

var app = angular.module('app',[]).directive('floatval', function(){
    return function(scope, element, attrs){
        var newInt = parseFloat(attrs.floatval);
        var n = newInt.toFixed(2);
    }
});

I'm stuck here as I dont know how to now reflect this new value in the place of the original scope {{somevariable}}

Answer 1

You can specify the scope of your directive. This way two-way binding is setup.

var app = angular.module('app',[]).directive('floatval', function(){
    return {
        scope: {
            floatval: '='
        },
        link: function(scope, element, attrs){
            scope.floatval = parseFloat(scope.floatval).toFixed(2);
        }
    };
});

Then you need to change your HTML <span floatval="someVariable">{{someVariable}}</span>

See https://code.angularjs.org/1.3.15/docs/guide/directive

Link to an example plnkr : http://plnkr.co/edit/aRyp1v9tGH7z8X28fewP?p=preview

Answer 2

Why don't you use built-in filters? https://docs.angularjs.org/api/ng/filter/number