AngularJS，如何将一个变量绑定到另外两个绑定变量的连接?

I am new to AngularJS and trying to build an AngularJS practice app, in which, the user will concatenate a url from multiple inputs, i.e. protocol, domain, path, param1, param2, param3... etc.

我是刚接触AngularJS的人，正在尝试构建一个AngularJS实践应用程序，在这个应用程序中，用户将从多个输入连接一个url，即协议、域、路径、param1、param2、param3……等。

And the app will create a link to the url:

app会创建到url的链接:

<a>{{protocol}}://{{domain}}{{path}}?{{param1}}&{{param2}}&{{param3}}</a>

Above url is used twice. Once on the href attribute, as well as the actual text. Now what I want to do is something like:

上面的url使用了两次。一旦在href属性，以及实际的文本。现在我想做的是:

<a href="{{url}}">{{url}}</a>

But I am not sure where to assign url. I tried below, and it worked, but doesn't seem correct.

但是我不确定在哪里分配url。我在下面试了试，它成功了，但似乎不正确。

<a href='{{url = protocol+"://"+domain+path+"?"+param1+"&"+param2+"&"+param3}}'>{{url}}</a>

Assuming that url is used many times in the app, where would be the most appropriate place to assign url?

假设在应用程序中多次使用url，那么在哪里指定url才是最合适的位置呢?

3 个解决方案

#1

You shouldn't assign scope variables in the view (the HTML) - it's only for reading them.

您不应该在视图(HTML)中分配范围变量——它只用于读取它们。

To make a new variable from inputs, add a ng-model to each of them and then in the controller define a method that makes a $scope variable from them e.g.

要从输入中创建一个新变量，请向每个输入中添加一个ng-model，然后在控制器中定义一个方法，该方法从输入中生成一个$scope变量，例如。

Your HTML form:

你的HTML表单:

<div ng-controller="MyCtrl">

    <input type="text" ng-model="urlParts.protocol">
    <input type="text" ng-model="urlParts.domain">
    <!-- etc -->
    <a ng-href="{{makeUrl()}}">{{makeUrl()}}</a>
</div>

JS:

function MyCtrl($scope) {
    $scope.urlParts = {};
    $scope.urlParts.protocol = ""; 
    $scope.urlParts.domain = ""; 
    // etc... 
    // These values will be updated when the user types in the input boxes

    $scope.makeUrl = function() {
      return $scope.urlParts.protocol + "://" + $scope.urlParts.domain + $scope.urlParts.path + "?" + $scope.urlParts.param1 + "&" + $scope.urlParts.param2 + "&" + $scope.urlParts.param3;
    }
}

#2

Another similar approach is to use ng-init directive to create a dynamic property which represents the concatenation of all those properties. You can call the function or just concatenate inline.

另一种类似的方法是使用ng-init指令创建一个动态属性，该属性表示所有这些属性的连接。您可以调用该函数，也可以将其连接到内联。

 <a ng-init="urlParts.url=makeUrl()" 
ng-href="urlParts.url">{{urlParts.url}}
</a>

<a ng-init="urlParts.url=urlParts.protocol + '://' + $scope.urlParts.domain..." 
    ng-href="urlParts.url">{{urlParts.url}}
    </a>

Reference: http://www.ozkary.com/2015/03/angularjs-ng-model-concatenate-model.html

参考:http://www.ozkary.com/2015/03/angularjs-ng-model-concatenate-model.html

Try It: http://plnkr.co/edit/PSvwCE?p=info

试一试:http://plnkr.co/edit/PSvwCE?p=info

#3

If you want to bind a dynamic url with href then you can manipulate you URL in ng-click or ng-mousedown event and bind to target element.

如果您想用href绑定一个动态url，那么您可以在ng-click或nmousedown事件中操作url并绑定到目标元素。

JS:

var goToLinkedPage = function (event, basePath, param1, param2, param 3) {
    var newState = basePath + "?" + param1 + "&" + param2 + "&" + param3;
    jQuery(event.target).attr('href',newState);
};

HTML:

<a ng-mousedown="goToLinkedPage($event, basePath, param1, param2, param3)"> Click Here </a>

#1