硒：
我是WebDriverJS的新手。我在Java中尝试过这种方法。
Long repaeted = 0l, scrollHeight = 0l, returnHeight = 0l;
while(true){
if (repaeted == 0) {
returnHeight = (Long) jse.executeScript("var scroll =document.documentElement.scrollHeight;window.scrollTo(0, scroll); return scroll;");
System.out.println("Height : "+scrollHeight +"\t Chnage : "+returnHeight+ "\t Repeated : "+repaeted);
scrollHeight = returnHeight;
}else {
returnHeight = (Long) jse.executeScript("var scroll = document.documentElement.scrollHeight;window.scrollTo(0, scroll); return scroll;");
System.out.println("Height : "+scrollHeight +"\t Chnage : "+returnHeight+ "\t Repeated : "+repaeted);
if (scrollHeight.intValue() == returnHeight.intValue()) {
System.out.println("Break.."+ returnHeight);
break;
} else { scrollHeight = returnHeight; }
}
repaeted++;
}
但是我在迭代循环时遇到webdriverjs的问题。
var webdriver = require('..'),
By = webdriver.By,
until = webdriver.until;
// make sure chromedriver can be found on your system PATH
var driver = new webdriver.Builder()
.forBrowser('chrome')
.withCapabilities(webdriver.Capabilities.chrome())
.build();
driver.get('https://in.yahoo.com/').then(function(){
var window = new webdriver.WebDriver.Window(driver);
window.maximize();
driver.manage().timeouts().implicitlyWait(1000 * 3);
})
.then(function(){
console.log('Entered');
var check = 0, count = 0
for(var i = 0; i< 50; i++){
//driver.sleep(1000 * 2);
driver.executeScript('var dynamicscroll = document.documentElement.scrollHeight;window.scrollTo(0, dynamicscroll);return dynamicscroll;').then(function(height){
console.log('Check : '+check+' Height : '+height +' Repeated : '+(count++));
if(check === 0 || check !== height){console.log('continue'); check = height; }
else { console.log('break'); i = 100; }
});
}
})
.then(null, function(err) {
console.error("An error was thrown! By Promise..." + err);
});
driver.quit();
在我的代码中我已经硬编码循环迭代直到50次，我想在滚动高度到达结束时退出/中断循环。在这种方法中，我想删除像java代码这样的硬编码，因为我不知道为滚动保持动态增加的其他应用程序迭代多少次。 例如，Facebook应用程序，雅虎新闻......
答案 0 :(得分：5)
滚动到动态页面的底部可能具有挑战性，具体取决于页面的实现方式。
首先，您必须使用滚动条找到容器，因为它可能与链接到window.scrollTo的容器不同。
然后通过增加scrollTop来滚动容器，直到scrollHeight变得稳定而没有待处理的请求。要检查是否存在待处理请求，请在页面具有JQuery时评估jQuery.active，或者XMLHttpRequest来监控send上的呼叫。
这是一个使用泛型函数滚动到页面底部多次或直到结束的示例：
var webdriver = require('selenium-webdriver');
var driver = new webdriver.Builder().forBrowser('chrome').build();
driver.get('https://groups.google.com/forum/#!search/webdriverjs');
// scroll to the bottom 3 times
driver.executeAsyncScript(scrollBottom, 3)
.then(n => console.log(`scrolled ${n} time(s)`));
// scroll to the bottom until the end
driver.executeAsyncScript(scrollBottom)
.then(n => console.log(`scrolled ${n} time(s)`));
function scrollBottom(){
var count = arguments[arguments.length - 2] || 0x7fffffff;
var callback = arguments[arguments.length - 1];
/* get the scrollable container */
var elm = document.elementFromPoint(window.innerWidth - 25, window.innerHeight / 2);
for ( ;elm && (++elm.scrollTop, !elm.scrollTop); elm=elm.parentElement);
elm = elm || document.documentElement;
/* hook XMLHttpRequest to monitor Ajax requests */
if (!('idle' in XMLHttpRequest)) (function(){
var n = 0, t = Date.now(), send = XMLHttpRequest.prototype.send;
var dispose = function(){ --n; t = Date.now(); };
var loadend = function(){ setTimeout(dispose, 1) };
XMLHttpRequest.idle = function() { return n > 0 ? 0 : Date.now() - t; };
XMLHttpRequest.prototype.send = function(){
++n;
this.addEventListener('loadend', loadend);
send.apply(this, arguments);
};
})();
/* scroll until steady scrollHeight or count of scroll and no pending request */
var i = 0, scrollHeight = -1, scrollTop = -1;
(function scroll(){
if ((scrollHeight === elm.scrollHeight || i === count) && XMLHttpRequest.idle() > 60)
return callback(i);
scrollTop = elm.scrollTop;
scrollHeight = elm.scrollHeight;
if (i < count)
i += (elm.scrollTop = 0x7fffffff, scrollTop !== elm.scrollTop);
setTimeout(scroll, 100);
})();
}
或者通过滚动直到高度在特定时间（此处为5秒）内不再增加：
function scrollBottom(){
var count = arguments[arguments.length - 2] || 0x7fffffff;
var callback = arguments[arguments.length - 1];
var timeout = 5000; /* 5 seconds timeout */
var i = 0;
/* get the scrollable container */
var elm = document.elementFromPoint(window.innerWidth - 25, window.innerHeight / 2);
for ( ;elm && (++elm.scrollTop, !elm.scrollTop); elm=elm.parentElement);
elm = elm || document.documentElement;
/* scroll while the height is increasing or until timeout */
(function scroll(){
var endtime = Date.now() + timeout;
var height = elm.scrollHeight;
elm.scrollTop = 0x7fffffff; /* scroll */
setTimeout(function check(){
if (Date.now() > endtime) /* returns if waited more than 5 sec */
callback(i);
else if (elm.scrollHeight == height) /* wait again if same height */
setTimeout(check, 60);
else if (++i === count) /* returns if scrolled the expected count */
callback(i);
else /* scroll again */
setTimeout(scroll, 60);
}, 250);
})();
}
答案 1 :(得分：1)
纯JavaScript：
在JavaScript中，我们可以使用setTimeout（）函数。它将在您指定的时间延迟后递归调用指定的函数。
我测试了google群组应用，其div标签垂直滚动动态增加。要加载内容我使用了5000的时间延迟。您可以在浏览器的控制台中使用以下网址测试此代码：https://groups.google.com/forum/#!search/webdrierjs。
var i = 0, height = 0, check = 0, t = null;
flow();
function run(arg){
var objDiv = document.querySelector('div.IVILX2C-b-F');
objDiv.scrollTop = objDiv.scrollHeight;
return objDiv.scrollHeight;
}
function flow() {
i++;
switch(i){
case 0: height = run(i);
sleep(5000);
break;
case -1: run(i);
clearTimeout(t); //stops flow
break;
default: check = run(i);
console.log('Return Height : '+check +' Count : '+i);
if(check === height){ i = -2;
console.log('Break message : '+i);
}else {
console.log('Changed...');
height = check;
}
sleep(5000);
break;
}
}
function sleep(delay) { t=setTimeout("flow()",delay);} //starts flow control again after time specified.
//function sleep(delay) { var start = new Date().getTime(); while (new Date().getTime() < start + delay); flow(); } // stops execution and then continues.
但即使我无法使用WebDriver / WebDriverJS运行此脚本，因为它不会在延迟时间内调用递归函数。
答案 2 :(得分：1)
根据经验，滚动到页面末尾的最快方法是查找页脚元素和movetoit，通常是#footer或.footer或只是footer选择器会执行此操作。 E.g：
footer = driver.findElement({id: "footer"});
driver.executeScript("arguments[0].scrollIntoView(false);", footer);
在无休止的情况下像Facebook，Twitter等流可能会在达到限制时阻止你，所以可以递归地将最大迭代与window.scrollTo(0, 300);结合起来，并在每次滚动后等待几秒钟。