以下是我的工作方式。

步骤1 - 确定仅在页面完全呈现后才出现的网页元素。我使用Chrome开发人员工具'Elements'视图显示了DOM视图。

Step 1 - Identify a web page element that only appears once the page is fully rendered. I did this using the Chrome developer tools 'Elements' view which shows the DOM view.

步骤2 - 在脚本中建立一个等待循环，轮询是否存在元素或该元素内的文本值。

Step 2 - Establish a wait loop in the script which polls for the existence of the element or the value of text inside that element.

# Element ID to check for in DOM
$elementID = "systemmessage"

# Text to match in elemend
$elementMatchText = "logged in"

# Timeout
$timeoutMilliseconds = 5000

$ie = New-Object -ComObject "InternetExplorer.Application"

# optional
$ie.Visible = $true

$ie.Navigate2("http://somewebpage")
$timeStart = Get-Date
$exitFlag = $false

do {

    sleep -milliseconds 100

    if ( $ie.ReadyState -eq 4 ) {

        $elementText = (($ie.Document).getElementByID($elementID )).innerText
        $elementMatch = $elementText -match $elementMatchText

        if ( $elementMatch ) { $loadTime = (Get-Date).subtract($timeStart) }

    }

    $timeout = ((Get-Date).subtract($timeStart)).TotalMilliseconds -gt $timeoutMilliseconds
    $exitFlag = $elementMatch -or $timeout

} until ( $exitFlag )

Write-Host "Match element found: $elementMatch"
Write-Host "Timeout: $timeout"
Write-Host "Load Time: $loadTime"