Question

我已经为表单控件创建了指令。对于required，如果值为空，则验证工作正常但我想在emptyDirective.js中设置为空和“-1”所以修改了selectControlDir。但是没有定义错误ctrl。

选择控制指令代码

function selectControlDir()
    {
        return {
            transclude: true,
            restrict: 'E',
            scope: {
              ngModel: '=',
              queObj: '='
            },
            template: '<div class="form-group">\n\
<label for="{{queObj._attributeName}}" class="col-sm-5 control-label">{{queObj._text}}</label>\n\
<div class="col-sm-6"><select {{queObj._attributeName}} ng-options="ans._value as ans._promptText for ans in queObj._answerOptions" ng-model="ngModel" ng-required="queObj._required" class="form-control {{queObj._pageAttributes.cssclass}}" name="{{queObj._attributeName}}" id="{{queObj._attributeName}}"></select>\n\
</div>'
            ,
            link: function (scope, element, attrs)
            {
                if(angular.isUndefined(scope.ngModel))
                {
                    scope.ngModel = scope.queObj._pageAttributes.defaultValue;
                }
                // add a parser that will process each time the value is
                // parsed into the model when the user updates it.
                ctrl.$parsers.unshift(function (value) {
                    if (value) {
                        // test and set the validity after update.
                        var valid = value.charAt(0) == '' || value.charAt(0) == '-1';
                        ctrl.$setValidity('required', valid);
                    }
                    // if it's valid, return the value to the model,
                    // otherwise return undefined.
                    return valid ? value : undefined;
                });
            }
        };
    }

我在这里缺少什么？有关完整代码https://plnkr.co/edit/GA74YHNFxFb0ARg16Sjj?p=preview

，请参阅plunker

如果我删除了此ctrl.$parsers.unshift代码，则会出现错误。

Answer 1

ctrl未定义，因为您错过了在指令中设置require属性：

return {
        transclude: true,
        restrict: 'E',
        require: 'ngModel',
        scope: {
          ngModel: '=',
          queObj: '='
        },
        template: '...'
        ,
        link: function (scope, element, attrs, ctrl)
        { 
            if(angular.isUndefined(scope.ngModel))
            {
                scope.ngModel = scope.queObj._pageAttributes.defaultValue;
            }
            // add a parser that will process each time the value is
            // parsed into the model when the user updates it.
            ctrl.$validators.required = (function (value) {
                var valueToTest = value || '';
                // if it's valid, return the value to the model,
                // otherwise return undefined.
                return !(valueToTest.charAt(0) == '' || valueToTest.charAt(0) == '-1');
            });
        }

}

在定义了require属性后，您可以访问链接功能中的ctrl

编辑：通过这种方式，双向绑定（ngModel：＆＃39; =＆＃39;）是不必要的

自定义验证无法使用Angular Js

1 个答案: