javascript - Uncaught Error : [$rootScope:infdig] when implementing an elapsed time calculator

Question

我在运行时间计算器的代码中的浏览器控制台中收到此错误:

Uncaught Error: [$rootScope:infdig]

我从应用程序启动的当前时间计算耗时。

这是我的 html:

<div ng-app="time">
  <div ng-controller="Ctrl2">
    Elapsed time: <span my-current-time="[date,format]"></span>
  </div>
</div>

这是 JavaScript 代码:

function Ctrl2($scope) {
  $scope.date = new Date();
  $scope.format = 'M/d/yy h:mm:ss a';
}

angular.module('time', [])
  // Register the 'myCurrentTime' directive factory method.
  // We inject $timeout and dateFilter service since the factory method is DI.
  .directive('myCurrentTime', function($timeout, dateFilter) {
    // return the directive link function. (compile function not needed)
    return function(scope, element, attrs) {
      var format,  // date format
          timeoutId; // timeoutId, so that we can cancel the time updates
      var since;   

      // used to update the UI
      function updateTime() {
        element.text(dateFilter(since, format));
        element.text( (((new Date()).getTime() - since.getTime())/(1000*60)%60) + " minutes, since " + dateFilter(since, format));  
      }

      // watch the expression, and update the UI on change.
      //scope.$watch(attrs.myCurrentTime, function(value) {
       // format = value;
       // updateTime();
      //});

      scope.$watch(attrs.myCurrentTime, function(value) {
          since = value[0];
          format = value[1];
          updateTime();
      });

      // schedule update in one second
      function updateLater() {
        // save the timeoutId for canceling
        timeoutId = $timeout(function() {
          updateTime(); // update DOM
          updateLater(); // schedule another update
        }, 1000);
      }

      // listen on DOM destroy (removal) event, and cancel the next UI update
      // to prevent updating time ofter the DOM element was removed.
      element.bind('$destroy', function() {
        $timeout.cancel(timeoutId);
      });

      updateLater(); // kick off the UI update process.
    }
  });

请帮忙，我也做了 fiddle 看看代码

http://jsfiddle.net/sojharo/9FnU2/1/

Answer 1

看来我已经找到了问题所在。我假设 angular 在每次评估时都会创建新数组，因此它总是会触发观察者

function Ctrl2($scope) { $scope.date = new Date(); $scope.format = 'M/d/yy h:mm:ss a'; $scope.options = [$scope.date, $scope.format]; //<--line added }

<div ng-app="time"> <div ng-controller="Ctrl2"> Elapsed time: <span my-current-time="options"></span> //<-- binding change. </div> </div>

updated fiddle

已添加

也不确定您是否真的需要此 watch 功能。请记住， watch 在您的情况下适用于整个阵列而不是内部元素。您可以提取值 scope.$eval(attrs.myCurrentTime) .