Forcing a ng-src reload

Question

How can I force angularjs to reload an image with an ng-src attribute, when the url of the image has not changed, but its contents has?

        
                      

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Answer 1

An "angular approach" could be creating your own filter to add a random querystring parameter to the image URL.

Something like this:

.filter("randomSrc", function () {
    return function (input) {
        if (input) {
            var sep = input.indexOf("?") != -1 ? "&" : "?";
            return input + sep + "r=" + Math.round(Math.random() * 999999);
        }
    }
})

Then you can use it like this:

<img ng-src="{{yourImageUrl | randomSrc}}" />

Answer 2

I resorted to make a directive to put random param in the src, but only if the image changes, so I don't mess that much with the caching.

I use it to update the user's profile pic in the navbar when they update it via AJAX, which doesn't happen that often.

(function() {
  "use strict";

  angular
    .module("exampleApp", [])
    .directive("eaImgSrc", directiveConstructor);

  function directiveConstructor() {
    return { link: link };

    function link(scope, element, attrs) {
      scope.$watch(attrs.eaImgSrc, function(currentSrc, oldSrc) {
        if (currentSrc) {
          // check currentSrc is not a data url,
          // since you can't append a param to that
          if (oldSrc && !currentSrc.match(/^data/)) {
            setSrc(currentSrc + "?=" + new Date().getTime());
          } else {
            setSrc(currentSrc);
          }
        } else {
          setSrc(null);
        }
      })

      function setSrc(src) { element[0].src = src; }
    }
  }
})();

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>

<div ng-app="exampleApp">
  <div>
    <img ea-img-src="src"></img>
  </div>

  <button ng-click="src = 'http://placehold.it/100x100/FF0000'">IMG 1</button>
  <button ng-click="src = 'http://placehold.it/100x100/0000FF'">IMG 2</button>
  <button ng-click="src = 'http://placehold.it/100x100/00FF00'">IMG 3</button>
</div>

Answer 3

An easy workaround is to append a unique timestamp to ng-src to force image reload as follows:

$scope.$apply(function () {
    $scope.imageUrl = $scope.imageUrl + '?' + new Date().getTime();
});

or

angular.module('ngSrcDemo', [])
    .controller('AppCtrl', ['$scope', function ($scope) {
    $scope.app = {
        imageUrl: "http://example.com/img.png"
    };
    var random = (new Date()).toString();
    $scope.imageSource = $scope.app.imageUrl + "?cb=" + random;
}]);

Answer 4

Try This

app.controller('ctrl', ['$scope', 'R4aFact', function($scope, R4aFact){
$scope.clickReplace = function() {
    R4aFact.uploadReplace($scope.imgfile, $scope.pid).then(function(response){
        $scope.urlprofilephoto  = response + "?" + new Date().getTime(); //here response is ur image name with path.
    });
}
 }])

Answer 5

Perhaps it could be as simple as adding a decache query string to the image URL? ie.

var imageUrl = 'http://i.imgur.com/SVFyXFX.jpg';
$scope.decachedImageUrl = imageUrl + '?decache=' + Math.random();

This should force it to reload.