json - 类选择器上的每个循环出现 Cheerio 错误 - TypeError : Cannot set property 'range' of undefined

Question

我正在请求应用程序上进行简单的 Cheerio 解析。不确定为什么在尝试设置数组时会出现此未定义的错误，但我猜测该值不存在可供设置。

        var $ = cheerio.load(body);

        var json = [  
            { "range": "", "address": "", "state": "", "zip": "", "info": "" }
        ];

        $('.findCourse').each(function (i, elem) {
            // Range Name
            console.log("iteration - ", i);
            console.log("name - ", $(this).text().trim());
            json[i].range = $(this).text().trim();
        });

这是我的控制台响应，它读取并设置在抓取的 html 中找到的前两项。

iteration -  0
name -  Pollock's Ferry Hunting Club Inc.
iteration -  1
name -  Eagle 1

TypeError: Cannot set property 'range' of undefined

at Object.<anonymous> (/usr/local/node_app/server.js:30:31)
  at exports.each (/usr/local/node_app/node_modules/cheerio/lib/api/traversing.js:267:24)
at Request.request.post.form.__EVENTTARGET [as _callback] (/usr/local/node_app/server.js:26:30)
at Request.self.callback (/usr/local/node_app/node_modules/request/request.js:121:22)
at Request.EventEmitter.emit (events.js:98:17)
at Request.<anonymous> (/usr/local/node_app/node_modules/request/request.js:978:14)
at Request.EventEmitter.emit (events.js:117:20)
at IncomingMessage.<anonymous> (/usr/local/node_app/node_modules/request/request.js:929:12)
at IncomingMessage.EventEmitter.emit (events.js:117:20)
at _stream_readable.js:920:16 1 May 23:02:57 - [nodemon] app crashed - waiting for file changes before starting...

Answer 1

发现问题了。在抛出引用错误之前正在执行调试语句。

简单的 javascript 数组问题，我试图将新元素插入数组中不存在的位置。

这是我的修复。

    var $ = cheerio.load(body);
    var json = [];

    $('.findCourse').each(function (i, elem) {
        // Range Name
        json.push({});
        json[i].range = $(this).text().trim();
    });