javascript AngularJS - 禁用 ng 的错误？不更新新值
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AngularJS - bug with ng-disabled? Not updating with new values
提问by Daniel Jamrozik
I'm somewhat new to angular and have come across a very weird problem, I'm sure others have too.
我对 angular 有点陌生，遇到了一个非常奇怪的问题，我相信其他人也有。
Let's say that this is the code for my button:
假设这是我的按钮的代码：
<button type="submit" ng-click="submit(something)" id="coolButton"
ng-disabled="type === 0 || code === ''"
>Check-In</button>
So, basically if either type is 0 or code is nothing (no text), then this button will be disabled.
所以，基本上如果任一类型为 0 或代码什么都没有（没有文本），那么这个按钮将被禁用。
Now's here where my problem starts: If I load the page with type = 0and code = '', then sure enough it's disabled. If, I change both of these values then of course the button will be enabled.
现在是我的问题开始的地方：如果我使用type = 0和加载页面code = ''，那么肯定它已被禁用。如果我更改了这两个值，那么当然会启用该按钮。
However, if I change the values back to 0and '', then the button won't become disabled again. I know for a fact that the values are in fact 0 and '' as I've printed their values out on the page.
但是，如果我将值改回0and ''，则该按钮将不会再次被禁用。我知道这些值实际上是 0 和 '' 因为我已经在页面上打印了它们的值。
What could be causing ng-disabledto not run the expression again?
什么可能导致ng-disabled不再运行表达式？
采纳答案by Radim K?hler
I created working plunker herefor you, to check that scenario described above is working:
我在这里为您创建了工作 plunker，以检查上述场景是否有效：
<div ng-controller="HomeCtrl">
<button type="submit"
ng-click="submit(something)"
id="coolButton"
ng-disabled="type === 0 || code === ''"
>Check-In</button><br />
<div>type: <input ng-model="type" type="number" /></div>
<div>code: <input ng-model="code" type="text" /></div>
<div>is type equal zero: {{type === 0 }}</div>
<div>is type code empty: {{code === '' }}</div>
</div>
<script type="text/javascript">
var app = angular
.module('MyApp', [])
.controller('HomeCtrl', ['$scope', function ($scope) {
$scope.something = function(sth){alert(sth)};
$scope.type = 0;
$scope.code = "";
}])
</script>
Important parts here are inside of the controller, where we explicitly init the code and type. Otherwise both will start with undefined/null.
这里的重要部分在控制器内部，我们在那里显式地初始化代码和类型。否则两者都将以 undefined/null 开头。
Check it here
在这里检查
Also, I would strongly suggest to change that style of $scope.type, $scope.code. It could bring some surprising behaviour sooner or later...
另外，我强烈建议更改 $scope.type、$scope.code 的样式。它迟早会带来一些令人惊讶的行为......
We should use some kind of Model cluster, which represents some reference which could be easily passed and does have a dot (see: https://stackoverflow.com/a/21882900/1679310)
我们应该使用某种模型集群，它代表一些可以轻松传递的引用并且确实有一个点（参见：https: //stackoverflow.com/a/21882900/1679310）
// controller
$scope.Model = {
type : 0,
code : '',
}
// directive ngDisabled in the view
ng-disabled="Model.type === 0 || Model.code === ''"
