在 ng-repeat 中动态添加指令 [英] dynamically adding directives in ng-repeat

问题描述

我正在尝试在 ng-repeat 中动态添加不同的指令，但是输出没有被解释为指令.

I am trying to dynamically add different directives in an ng-repeat however the output is not being interpreted as directives.

我在这里添加了一个简单的例子:http://plnkr.co/edit/6pREpoqvmcnJJWzhZZKq

I've added a simple example here: http://plnkr.co/edit/6pREpoqvmcnJJWzhZZKq

控制器:

$scope.colors = [{name:"red"}, {name: "blue"}, {name:"yellow"}]; 

指令:

app.directive("red", function () {
    return {
        restrict: 'C',
        template: "RED directive"
    }
});

HTML:

<ul>
  <li ng-repeat="color in colors">
    <span class="{{color.name}}"></span>
  </li>
</ul>

如何让 angular 拾取通过 ng-repeat 输出的 class 中指定的指令?

How do I make angular pick up the directive specified in the class that is output via ng-repeat?

推荐答案

我知道这是一个老问题，但 google 把我带到这里，我不喜欢这里的答案......它们似乎对于某些事情来说真的很复杂应该很简单.所以我创建了这个指令:

I know this is an old question, but google brought me here, and I didn't like the answers here... They seemed really complicated for something that should be simple. So I created this directive:

***** 新内容 *****

***** NEW CONTENT *****

我已经使这个指令更通用，支持解析的(典型的角度值)属性"属性.

I've since made this directive more generic, supporting a parsed (the typical angular value) "attributes" attribute.

/**
 * Author: Eric Ferreira <http://stackoverflow.com/users/2954747/eric-ferreira> ©2016
 *
 * This directive takes an attribute object or string and adds it to the element
 *   before compilation is done. It doesn't remove any attributes, so all
 *   pre-added attributes will remain.
 *
 * @param {Object<String, String>?} attributes - object of attributes and values
 */
.directive('attributes', function attributesDirective($compile, $parse) {
    'use strict';

    return {
        priority: 999,
        terminal: true,
        restrict: 'A',
        compile: function attributesCompile() {
            return function attributesLink($scope, element, attributes) {
                function parseAttr(key, value) {
                    function convertToDashes(match) {
                        return match[0] + '-' + match[1].toLowerCase();
                    }

                    attributes.$set(key.replace(/([a-z][A-Z])/g, convertToDashes), value !== undefined && value !== null ? value : '');
                }

                var passedAttributes = $parse(attributes.attributes)($scope);

                if (passedAttributes !== null && passedAttributes !== undefined) {
                    if (typeof passedAttributes === 'object') {
                        for (var subkey in passedAttributes) {
                            parseAttr(subkey, passedAttributes[subkey]);
                        }
                    } else if (typeof passedAttributes === 'string') {
                        parseAttr(passedAttributes, null);
                    }
                }

                $compile(element, null, 999)($scope);
            };
        }
    };
});

对于 OP 的用例，您可以这样做:

For the OP's use case, you could do:

<li ng-repeat="color in colors">
    <span attributes="{'class': color.name}"></span>
</li>

或者将其用作属性指令:

Or to use it as an attribute directive:

<li ng-repeat="color in colors">
    <span attributes="color.name"></span>
</li>

***** 结束新内容******

***** END NEW CONTENT ******

/**
 * Author: Eric Ferreira <http://stackoverflow.com/users/2954747/eric-ferreira> ©2015
 *
 * This directive will simply take a string directive name and do a simple compilation.
 * For anything more complex, more work is needed.
 */
angular.module('attributes', [])

.directive('directive', function($compile, $interpolate) {
    return {
        template: '',
        link: function($scope, element, attributes) {
            element.append($compile('<div ' + attributes.directive + '></div>')($scope));
        }
    };
})

;

对于这个问题的具体情况，可以稍微重写指令，使其按类将指令应用于跨度，如下所示:

For the specific case in this question, one can just rewrite the directive a bit to make it apply the directive to a span by class, as so:

angular.module('attributes', [])

.directive('directive', function($compile, $interpolate) {
    return {
        template: '',
        link: function($scope, element, attributes) {
            element.replaceWith($compile('<span class=\"' + attributes.directive + '\"></span>')($scope));
        }
    };
})

;

然后你可以在任何地方使用它并动态地按名称选择指令.像这样使用它:

Then you can use this anywhere and select a directive by name dynamically. Use it like so:

<li ng-repeat="color in colors">
    <span directive="{{color.name}}"></span>
</li>

我特意让这个指令简单明了.您可能(并且可能会)不得不重新编写它以满足您的需要.

I purposely kept this directive simple and straightforward. You may (and probably will) have to reword it to fit your needs.

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