淘汰赛js CSS绑定

Question

我在我的项目中使用 Knockout js，我需要将多个 css 类名称添加到特定标签。下面是我的代码，我有三个不同的类，我如何将它添加到 knockout css 绑定中，请建议。

<img data-bind="attr: { src:ProfileImageSrcName }" class="tabUser profile-Image tabpic" />

Answer 1

你可以像下面这样绑定css。

var vm = {
  profileImageSrcName: ko.observable('http://cumbriaskills.wdfiles.com/local--files/files:images/metro_128_chrome.png'),
  isProfilePic: ko.observable(true),
  isTab: ko.observable(true),
  toggleProfile: function() { vm.isProfilePic(!vm.isProfilePic()); },
  toggleTab: function() { vm.isTab(!vm.isTab()); }
};

ko.applyBindings(vm);

.tabUser { width: 100px; height: 100px; object-fit: contain; }
.profile-image { border-radius: 100% } 
.tabPic { box-shadow: 0 2px 6px rgba(0,0,0,0.4) }

<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.4.2/knockout-min.js"></script>
<img data-bind="attr: { src: profileImageSrcName }, 
                css: { 
                  'profile-image': isProfilePic, /* single class */
                  'tabUser tabPic': isTab  /* multiple classes */
                }" />
<br><br>
<button data-bind="click: toggleProfile">Toggle "profile-image" Class</button><br>
<button data-bind="click: toggleTab">Toggle "tabUser" and "tabPic" Classes</button>

Answer 2

使用css绑定来分配多个类名。

http://knockoutjs.com/documentation/css-binding.html

var masterVM = (function () {
  var self = this;      
  self.classNames = ko.pureComputed(function(){
    return "className1 className2 className3";
  }, self);
})();

ko.applyBindings(masterVM); 

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>

<div class="existingClass" data-bind="css: classNames">
  Inspect this element to see list of the 4 class names.
</div>