我使用nightmare.js刮公共记录,我只是想让刮板等待下一页加载。我正在抓取搜索结果,我按下了一个下一个按钮(显然)进入下一页。我无法使用nightmare.wait(someConstTime)
准确地等待下一页加载,因为有时someConstTime
比下一页加载所用的时间要短(尽管它总是在30秒以内)。我也不能使用nightmare.wait(selector)
,因为相同的选择器总是出现在所有结果页面上。在这种情况下,噩梦基本上不会等待,因为选择器已经存在(在我已经抓取的页面上),所以它会继续多次刮同一页面,除非新页面在下一个循环之前加载。点击链接后获取梦魇等待下一页加载
点击下一步按钮后,如何有条件地等待下一页加载?
如果我能想出如何 - 我的“显示#至##项#”比较当前页面(currentPageStatus
)到最后一个已知值(lastPageStatus
)的指示,等到它们是不同的(因此下一页加载)。
我会做,使用从https://stackoverflow.com/a/36734481/3491991该代码但这需要经过lastPageStatus
到deferredWait
(我不能图出)。
这里是到目前为止,我已经得到了代码:
// Load dependencies
//const { csvFormat } = require('d3-dsv');
const Nightmare = require('nightmare');
const fs = require('fs');
var vo = require('vo');
const START = 'http://propertytax.peoriacounty.org';
var parcelPrefixes = ["01","02","03","04","05","06","07","08","09","10",
"11","12","13","14","15","16","17","18","19"]
vo(main)(function(err, result) {
if (err) throw err;
});
function* main() {
var nightmare = Nightmare(),
currentPage = 0;
// Go to Peoria Tax Records Search
try {
yield nightmare
.goto(START)
.wait('input[name="property_key"]')
.insert('input[name="property_key"]', parcelPrefixes[0])
// Click search button (#btn btn-success)
.click('.btn.btn-success')
} catch(e) {
console.error(e)
}
// Get parcel numbers ten at a time
try {
yield nightmare
.wait('.sorting_1')
isLastPage = yield nightmare.visible('.paginate_button.next.disabled')
while (!isLastPage) {
console.log('The current page should be: ', currentPage); // Display page status
try {
const result = yield nightmare
.evaluate(() => {
return [...document.querySelectorAll('.sorting_1')]
.map(el => el.innerText);
})
// Save property numbers
// fs.appendFile('parcels.txt', result, (err) => {
// if (err) throw err;
// console.log('The "data to append" was appended to file!');
// });
} catch(e) {
console.error(e);
return undefined;
}
yield nightmare
// Click next page button
.click('.paginate_button.next')
// ************* THIS IS WHERE I NEED HELP *************** BEGIN
// Wait for next page to load before continue while loop
try {
const currentPageStatus = yield nightmare
.evaluate(() => {
return document.querySelector('.dataTables_info').innerText;
})
console.log(currentPageStatus);
} catch(e) {
console.error(e);
return undefined;
}
// ************* THIS IS WHERE I NEED HELP *************** END
currentPage++;
isLastPage = yield nightmare.visible('.paginate_button.next.disabled')
}
} catch(e) {
console.error(e)
}
yield nightmare.end();
}