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How to change a CSS property dynamically in Angula

2019-02-17 15:38发布

问题:

Right now I have a background image URL hard-coded into CSS. I'd like to dynamically choose a background image using logic in AngularJS. Here is what I currently have:

HTML

<div class="offer-detail-image-div"><div>

CSS

.offer-detail-image-div {
  position: relative;
  display: block;
  overflow: hidden;
  max-width: 800px;
  min-height: 450px;
  min-width: 700px;
  margin-right: auto;
  margin-left: auto;
  padding-right: 25px;
  padding-left: 25px;
  -webkit-box-flex: 1;
  -webkit-flex: 1;
  -ms-flex: 1;
  flex: 1;
  border-radius: 5px;
  background-image: url('/assets/images/118k2d049mjbql83.jpg');
  background-position: 0px 0px;
  background-size: cover;
  background-repeat: no-repeat;
}

As you can see, the background image in the CSS references a specific file location. I want to be able to programmatically determine the location of the image URL. I really don't know where to begin. I do not know JQuery. Thank you.

回答1:

You can use ng-style to dynamically change a CSS class property using AngularJS.

Hope this ng-style example will help you to understand the concept at least.

More information for ngStyle

var myApp = angular.module('myApp', []);
myApp.controller("myAppCtrl", ["$scope", function($scope) {
      $scope.colors = ['#C1D786', '#BF3978', '#15A0C6', '#9A2BC3'];
      $scope.style = function(value) {
          return { "background-color": value };
      }
}]);
ul{
  list-style-type: none;
  color: #fff;
}
li{
  padding: 10px;
  text-align: center;
}
.original{
  background-color: red;
}
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<body ng-app="myApp">
<div ng-controller="myAppCtrl">
  <div class="container">
    <div class="row">
      <div class="span12">
        <ul>
          <li ng-repeat="color in colors">
            <h4 class="original" ng-style="style(color)"> {{ color }}</h4>
          </li>
        </ul>
      </div>
    </div>
  </div>
</div>
</body>

Edit-1

You can change the background-image: URL by following way.

$scope.style = function(value) {
   return { 'background-image': 'url(' + value+')' };
}


回答2:

You can use ng-class : documation. If you want to do it in your directive check directive - attr : attr.



回答3:

You can use [ngStyle] directly. It's a map, so you can directly address one of its elements like so: [ngStyle.CSS_PROPERTY_NAME]

For example:

<div class="offer-detail-image-div"
     [ngStyle.background-image]="'url(' + backgroundSrc + ')'">Hello World!</div>

Also, for serving assets, Angular has the bypassSecurityTrustStyle utility function that can come in handy when serving up assets dynamically.



回答4:

enter the size in textbox you can see box changes height and width

<!DOCTYPE html>
<html>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.4/angular.min.js"></script>
<body>

<p>Change the value of the input field:</p>

<div ng-app="" >

<input  ng-model="myCol" type="textbox">

<div style="background-color:red; width:{{myCol}}px; height:{{myCol}}px;"> </div>


</div>


</body>
</html>