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AngularJS - Value attribute on an input text box is ignored when there is a ng-model used?

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How do you use NG value?

The AngularJS ng-value directive is used to set the value attribute of an input element, or a select element. It is mainly used on <radio> and <option> elements to set the bound values when these elements are selected. It is supported by <input> and <select> elements.

What is NG-model used for?

The ng-model directive binds the value of HTML controls (input, select, textarea) to application data.

Can we use NG-model for Div?

NgModel expects the bound element to have a value property, which div s don't have. That's why you get the No value accessor error. I don't know if the input event is supported on all browsers for contenteditable . You could always bind to some keyboard event instead.

What is NG-model in HTML?

The ng-model directive binds an HTML form element to a variable in the scope. If the variable does not exist in the scope, it will be created.


That's desired behavior, you should define the model in the controller, not in the view.

<div ng-controller="Main">
  <input type="text" ng-model="rootFolders">
</div>


function Main($scope) {
  $scope.rootFolders = 'bob';
}

Vojta described the "Angular way", but if you really need to make this work, @urbanek recently posted a workaround using ng-init:

<input type="text" ng-model="rootFolders" ng-init="rootFolders='Bob'" value="Bob">

https://groups.google.com/d/msg/angular/Hn3eztNHFXw/wk3HyOl9fhcJ


Overriding the input directive does seem to do the job. I made some minor alterations to Dan Hunsaker's code:

  • Added a check for ngModel before trying to use $parse().assign() on fields without a ngModel attributes.
  • Corrected the assign() function param order.
app.directive('input', function ($parse) {
  return {
    restrict: 'E',
    require: '?ngModel',
    link: function (scope, element, attrs) {
      if (attrs.ngModel && attrs.value) {
        $parse(attrs.ngModel).assign(scope, attrs.value);
      }
    }
  };
});

The Angular way

The correct Angular way to do this is to write a single page app, AJAX in the form template, then populate it dynamically from the model. The model is not populated from the form by default because the model is the single source of truth. Instead Angular will go the other way and try to populate the form from the model.

If however, you don't have time to start over from scratch

If you have an app written, this might involve some fairly hefty architectural changes. If you're trying to use Angular to enhance an existing form, rather than constructing an entire single page app from scratch, you can pull the value from the form and store it in the scope at link time using a directive. Angular will then bind the value in the scope back to the form and keep it in sync.

Using a directive

You can use a relatively simple directive to pull the value from the form and load it in to the current scope. Here I've defined an initFromForm directive.

var myApp = angular.module("myApp", ['initFromForm']);

angular.module('initFromForm', [])
  .directive("initFromForm", function ($parse) {
    return {
      link: function (scope, element, attrs) {
        var attr = attrs.initFromForm || attrs.ngModel || element.attrs('name'),
        val = attrs.value;
        if (attrs.type === "number") {val = parseInt(val)}
        $parse(attr).assign(scope, val);
      }
    };
  });

You can see I've defined a couple of fallbacks to get a model name. You can use this directive in conjunction with the ngModel directive, or bind to something other than $scope if you prefer.

Use it like this:

<input name="test" ng-model="toaster.test" value="hello" init-from-form />
{{toaster.test}}

Note this will also work with textareas, and select dropdowns.

<textarea name="test" ng-model="toaster.test" init-from-form>hello</textarea>
{{toaster.test}}

Update: My original answer involved having the controller contain DOM-aware code, which breaks Angular conventions in favor of HTML. @dmackerman mentioned directives in a comment on my answer, and I completely missed that until just now. With that input, here's the right way to do this without breaking Angular or HTML conventions:


There's also a way to get both - grab the value of the element and use that to update the model in a directive:

<div ng-controller="Main">
    <input type="text" id="rootFolder" ng-model="rootFolders" disabled="disabled" value="Bob" size="40" />
</div>

and then:

app.directive('input', ['$parse', function ($parse) {
    return {
        restrict: 'E',
        require: '?ngModel',
        link: function (scope, element, attrs) {
            if(attrs.value) {
                $parse(attrs.ngModel).assign(scope, attrs.value);
            }
        }
    };
}]);

You can of course modify the above directive to do more with the value attribute before setting the model to its value, including using $parse(attrs.value, scope) to treat the value attribute as an Angular expression (though I'd probably use a different [custom] attribute for that, personally, so the standard HTML attributes are consistently treated as constants).

Also, there is a similar question over at Making data templated in available to ng-model which may also be of interest.


If you use AngularJs ngModel directive, remember that the value of value attribute does not bind on ngModel field.You have to init it by yourself and the best way to do it,is

<input type="text"
       id="rootFolder"
       ng-init="rootFolders = 'Bob'"
       ng-model="rootFolders"
       disabled="disabled"
       value="Bob"
       size="40"/>