该
.map功能仅在阵列上可用。
看起来好像
data不是您期望的格式（它是{}但您期望[]）。
this.setState({data: data});应该
this.setState({data: data.conversations});检查将“数据”设置为哪种类型，并确保它是一个数组。
修改后的代码，并提供一些建议（propType验证和clearInterval）：
var converter = new Showdown.converter();var Conversation = React.createClass({ render: function() { var rawMarkup = converter.makeHtml(this.props.children.toString()); return ( <div className="conversation panel panel-default"> <div className="panel-heading"> <h3 className="panel-title"> {this.props.id} {this.props.last_message_snippet} {this.props.other_user_id} </h3> </div> <div className="panel-body"> <span dangerouslySetInnerHTML={{__html: rawMarkup}} /> </div> </div> ); }});var ConversationList = React.createClass({ // Make sure this.props.data is an array propTypes: { data: React.PropTypes.array.isRequired }, render: function() { window.foo = this.props.data; var conversationNodes = this.props.data.map(function(conversation, index) { return ( <Conversation id={conversation.id} key={index}> last_message_snippet={conversation.last_message_snippet} other_user_id={conversation.other_user_id} </Conversation> ); }); return ( <div className="conversationList"> {conversationNodes} </div> ); }});var ConversationBox = React.createClass({ loadConversationsFromServer: function() { return $.ajax({ url: this.props.url, dataType: 'json', success: function(data) { this.setState({data: data.conversations}); }.bind(this), error: function(xhr, status, err) { console.error(this.props.url, status, err.toString()); }.bind(this) }); }, getInitialState: function() { return {data: []}; }, componentWillMount: function() { this.intervals = []; }, setInterval: function() { this.intervals.push(setInterval.apply(null, arguments)); }, componentWillUnmount: function() { this.intervals.map(clearInterval); }, componentDidMount: function() { this.loadConversationsFromServer(); this.setInterval(this.loadConversationsFromServer, this.props.pollInterval); }, render: function() { return ( <div className="conversationBox"> <h1>Conversations</h1> <ConversationList data={this.state.data} /> </div> ); }});$(document).on("page:change", function() { var $content = $("#content"); if ($content.length > 0) { React.render( <ConversationBox url="/conversations.json" pollInterval={20000} />, document.getElementById('content') ); }})
