警告：数组或迭代器中的每个子代都应具有唯一的“键”道具。 li中已添加的关键道具

Question

I am getting this warning after already adding the key prop to the li items in TodoItems : 我已经在TodoItems的li项目中添加了key道具后得到了这个警告：

Warning: Each child in an array or iterator should have a unique "key" prop. 警告：数组或迭代器中的每个子代都应具有唯一的“键”道具。 Check the render method of TodoItems 检查TodoItems的渲染方法

I have the following page: 我有以下页面：

<!DOCTYPE html>
<html>

<head>
    <title>todo-list</title>
    <script src="https://unpkg.com/react@15.3.2/dist/react.js"></script>
    <script src="https://unpkg.com/react-dom@15.3.2/dist/react-dom.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/babel-core/5.8.23/browser.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/react-router/4.0.0-beta.3/react-router.min.js"></script>

    <script src="https://cdnjs.cloudflare.com/ajax/libs/fixed-data-table/0.6.3/fixed-data-table.min.js"></script>
    <link href="https://cdnjs.cloudflare.com/ajax/libs/fixed-data-table/0.6.3/fixed-data-table.min.css" rel="stylesheet">

    <head>


        <body>
            <div style="margin-bottom: 35px">
                <a class="nav-link" href="/clock">clock</a>
                <a class="nav-link" href="/counter">counter</a>
                <a class="nav-link" href="/data-table-basic">data-table-basic</a>
                <a class="nav-link" href="/query-params-react-router">query-params-react-router</a>
                <a class="nav-link" href="/todo-list">todo-list</a>
                <a class="nav-link" href="/validated-form">validated-form</a>
            </div>


            <p>
                <a href="https://www.kirupa.com/react/simple_todo_app_react.htm" target="_blank">The tutorial link</a>
            </p>

            <div id="entry"></div>


            <script>
                function determineMode(filepath) {
                    var modeString = "ace/mode/" + filepath;
                    return modeString;
                }
            </script>

            <script src="/static/ace-builds2/src-noconflict/ace.js" type="text/javascript" charset="utf-8"></script>

            <script>
                var editor = ace.edit("editor");
                editor.getSession().setMode(determineMode('html'));
                editor.session.setNewLineMode("unix");
                editor.setTheme("ace/theme/monokai");
                editor.setFontSize(15);
            </script>

            <script type="text/babel">
                var destination = document.querySelector("#entry"); var TodoItems = React.createClass({ createTasks: function(item){ return this.props.entries.map(item => { return (
                <li data-bind-thisthing={item.key} key={item.key}>
                    <span>{item.text + " "} </span>
                    <a href="#" data-id="{item.id}" className="remove-filter" onClick={()=> this.props.remove(item)}
                        >
                            remove
                        </a>
                </li>
                ) }); }, render: function(){ return (
                <ul className="theList">
                    {this.createTasks()}
                </ul>
                ); } }); var TodoList = React.createClass({ getInitialState: function(){ return { items: [ 'If user clicks add button and input is empty, set a red border and focus the input box', 'Allow interactive DOM update of component when user edits code box', 'Allow categories for things like angular2, knockout, etc', 'Allow user to save new code snippets after starting in a sandbox', ] }; }, addItem: function(e) { var itemArray = this.state.items; if (this._inputElement.value.length > 0){ itemArray.push( { text: this._inputElement.value, key: this.state.items.length } ); this._inputElement.value = ""; this.setState({ items: itemArray }) } e.preventDefault(); }, // removing items from a list // http://stackoverflow.com/questions/27817241/how-to-remove-an-item-from-a-list-with-a-click-event-in-reactjs removeItem: function(item){ var items = this.state.items.filter(function(itm){ return item.key !== itm.key; }); this.setState({ items: items }); }, render: function() { return (
                <div className="todoListMain">
                    <div className="header">
                        <form onSubmit={this.addItem}>
                            <input ref={(a)=> this._inputElement = a} placeholder="enter task" />
                            <button type="submit">add</button>
                        </form>
                    </div>
                    <TodoItems remove={this.removeItem} entries={this.state.items} />
                </div>
                ); } }); ReactDOM.render(
                <div>
                    <TodoList/>
                </div>, destination );

            </script>
        </body>

</html>

Weird issues normally seem like this scope problems. 奇怪的问题通常看起来像是this范围问题。

Answer 1

Problem is initial state of TodoList. 问题是TodoList的初始状态。 createTasks function is expecting entries (props) an array containing objects where each object should have keys id , text and key but its getting array containing strings. createTasks函数期望条目（属性）为包含对象的数组，其中每个对象应具有键id ， text和key，但其获取数组包含字符串。

警告：数组或迭代器中的每个子代都应具有唯一的“键”道具。 li中已添加的关键道具

问题描述

1 个解决方案

解决方案1
2 已采纳 2017-02-01 07:01:11

警告：数组或迭代器中的每个子代都应具有唯一的“键”道具。 li中已添加的关键道具

问题描述

1 个解决方案

解决方案1 2 已采纳 2017-02-01 07:01:11

解决方案1
2 已采纳 2017-02-01 07:01:11