我有一个构造函数,它注册一个事件处理程序:
function MyConstructor(data, transport) {
this.data = data;
transport.on('data', function () {
alert(this.data);
});
}
// Mock transport object
var transport = {
on: function(event, callback) {
setTimeout(callback, 1000);
}
};
// called as
var obj = new MyConstructor('foo', transport);Run Code Online (Sandbox Code Playgroud)
但是,我无法data在回调中访问已创建对象的属性.它看起来this并不是指创建的对象,而是指另一个对象.
我还尝试使用对象方法而不是匿名函数:
function MyConstructor(data, transport) {
this.data = data;
transport.on('data', this.alert);
}
MyConstructor.prototype.alert = function() {
alert(this.name);
};
Run Code Online (Sandbox Code Playgroud)
但它表现出同样的问题.
如何访问正确的对象?
我正在尝试做教程:https://facebook.github.io/react/docs/tutorial.html
import React, { PropTypes } from 'react';
import classnames from 'classnames';
import styles from './CommentBox.css';
import withStyles from '../../decorators/withStyles';
import Link from '../../utils/Link';
import $ from 'jquery';
@withStyles(styles)
class CommentBox extends React.Component {
constructor() {
super();
this.state = {data: []};
}
loadCommentsFromServer() {
$.ajax({
url: this.props.url,
dataType: 'json',
cache: false,
success: function(data) {
this.setState({data: data});
}.bind(this),
error: function(xhr, status, err) {
console.error(this.props.url, status, err.toString());
}.bind(this)
})
}
componentDidMount() {
this.loadCommentsFromServer();
setInterval(this.loadCommentsFromServer, this.props.pollInterval);
}
render() {
let …Run Code Online (Sandbox Code Playgroud)