javascript - 重置作为参数传递的 select 的值

Question

我有一些相关选择，我想重置所有下一步

<select ng-change="applyChanges(model.v2)"
            ng-model="model.v1" name="v1"
            ng-options="v as v.Name for v in vs" class="form-control" required></select>

<select ng-change="applyChanges(model.v3)" ng-model="model.v2"
            name="v2"
            ng-options="vv as vv.Name for vv in model.v1.v2" class="form-control"
            required ng-disabled="!model.v1"></select>

但是如何重置 ng-change 方法上的选择值？

$scope.applyChanges = function (arg) {
        if (!_.isUndefined(arg)) {
            arg = "?";
        }

    };

Answer 1

在您的情况下，当您说 arg = '?' 时，您只是更改局部变量 arg 的值，即 model.v2 引用的值 没有改变。

因此将模型和要更改的属性作为参数传递给函数，例如

<select ng-change="applyChanges(model, 'v2')"
            ng-model="model.v1" name="v1"
            ng-options="v as v.Name for v in vs" class="form-control" required></select>

然后

$scope.applyChanges = function (model, prop) {
        if (!_.isUndefined(model[prop])) {
            model[prop] = "?";
        }
};

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