Question

我有长度和呼吸，基于o我正在计算面积（l * b），假设我有很多不同长度和呼吸的场，面积正在计算但我需要面积列的总和，所以如何添加一个新文本框中所有上述字段的总和???我需要所有num3（区域）的总和。

我的代码低于......

<!DOCTYPE html>
<html>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>
<body>
     <div ng-app="myapp" ng-controller="MainCtrl">
    <form  data-ng-repeat="choice in choices">
 Length:<input type="number" ng-model="num1"  />
 width: <input type="number" ng-model="num2"  />
 Area: <input id="area" type="number" ng-model="num3" placeholder="Area" value="{{ num1 * num2 }}" />
  <button  ng-show="$last" ng-click="removeChoice()">-</button>

    </form>
	<button  ng-click="addNewChoice()">Add fields</button>
    
</div>
    
     <script>
var app = angular.module('myapp', []);

  app.controller('MainCtrl', function($scope) {
 $scope.choices = [{id: 'choice1'}, {id: 'choice2'}];
  
  $scope.addNewChoice = function() {
    var newItemNo = $scope.choices.length+1;
    $scope.choices.push({'id':'choice'+newItemNo});
  };
    
  $scope.removeChoice = function() {
    var lastItem = $scope.choices.length-1;
    $scope.choices.splice(lastItem);
  };
 

  
});
</script>

</body>
</html>

Answer 1

在你的情况下，我不知道一个简单的解决方案。

你不能用value =“{{val + val2}}”来做，因为它只用于显示值而不是改变模型。

可能的解决方案：

<form  data-ng-repeat="choice in choices">
    Length:<input type="number" ng-model="choice.length"  />
    width: <input type="number" ng-model="choice.width"  />
    Area: <input id="area" type="number" placeholder="Area" value="{{ choice.length * choice.width }}" />
    <button  ng-show="$last" ng-click="removeChoice()">-</button>

</form>
<button  ng-click="addNewChoice()">Add fields</button>

Result : {{ sum() }}

在您的控制器中：

$scope.choices = [{id: 'choice1', length:0, width: 0}, {id: 'choice2', length:0, width: 0}];

  $scope.addNewChoice = function() {
    var newItemNo = $scope.choices.length+1;
    $scope.choices.push({'id':'choice'+newItemNo});
  };

  $scope.removeChoice = function() {
    var lastItem = $scope.choices.length-1;
    $scope.choices.splice(lastItem);
  };

    $scope.sum = function() {
        var sum = 0;
        angular.forEach($scope.choices, function(choice) {
            sum += choice.length * choice.width;
        });
        return sum;
    }

Answer 2

<form data-ng-repeat="item in choices">
    Length:
    <input type="number" ng-model="item.num1" /> width:
    <input type="number" ng-model="item.num2" /> Area:
    <input id="area" type="number" ng-model="num3" placeholder="Area" value="{{item.num1 * item.num2}}" />
    <button ng-show="$last" ng-click="removeChoice()">-</button>
</form>
<span data-ng-bind="'Total Area:' + total()"></span>
</br>
<button ng-click="addNewChoice()">Add fields</button>



  $scope.total = function() {
            var total = 0;
            angular.forEach($scope.choices, function(item) {
                total += item.num1 * item.num2;
            })
            return total;
        }

angularjs中所有sum列的总和

2 个答案: