Powershell：通过InternetExplorer.Application使用jQuery [英] Powershell: Using jQuery through InternetExplorer.Application

问题描述

我按照这篇文章说明了使用jQuery来调用Internet Explorer COM对象。虽然作者使用Python，我想在Powershell中做类似的操作。

I followed this article, explaining how to spice up an Internet Explorer COM-Object with jQuery. While the author used Python, I want to do something similar in Powershell.

现在我有这个代码：

function addJQuery ($browser) {
    $url="https://ajax.googleapis.com/ajax/libs/jquery/1.4.3/jquery.min.js"

    $document = $browser.document
    $window = $document.parentWindow
    $head = @($document.getElementsByTagName("head"))[0]
    $script = $document.createElement("script")
    $script.type = "text/javascript"
    $script.src = $url
    $head.appendChild($script)
    while (!$window.jQuery) {
        sleep -milliseconds 100
    }
    return $window.jQuery
}

$ie = New-Object -comobject InternetExplorer.Application
$ie.visible = $true
$ie.Navigate("https://some.site.com")
while ($ie.busy) {start-sleep -milliseconds 500}
$j = addJQuery $ie

通过Fiddler和通过document.scripts集合，我验证了文件被下载。然而，脚本睡着了，当我尝试输出$ window.jQuery它在Powershell ISE控制台中什么都不打印。

With Fiddler and via the document.scripts collection I verified that the file gets downloaded. However, the script sleeps forever and when I try to output $window.jQuery it prints nothing in the Powershell ISE console.

脚本仍然正确加载，因为jQuery-函数可以从浏览器的控制台或通过execScript（）调用。

The Script is nevertheless correctly loaded, since jQuery-Functions can be called from the browser's console or via execScript().

似乎问题是，通过$ ie.document可用的DOM表示不更新DOM更改是通过JavaScript进行的。但是，在Powershell中，Internet Explorer COM对象不应该像在Python中一样工作。

It seems the problem is that the DOM-representation available via $ie.document isn't updated when DOM-changes are made via JavaScript. But shouldn't the Internet Explorer COM-Object behave the same way in Powershell as it does in Python?

推荐答案

code> while 循环，表达式（！$ window.jQuery）总是返回 true 因为 $ window 是一个 ComObject ，COM对象不像JavaScript对象一样是expandos，所以即使 window.jQuery 存在于JavaScript中，它不会自动在PowerShell中的 $ window 对象上可见。

In your while loop, the expression (!$window.jQuery) always returns true because $window is a ComObject and COM Objects are not expandos like JavaScript objects, so even if window.jQuery exists in JavaScript, it won't automatically become visible on the $window object in PowerShell.

我真的找不到一个解决方法，使jQuery 对象在powershell中可用，我也有兴趣知道是否有办法做到这一点。请参见此和此< a>我创建的问题。

I really couldn't find a workaround to make jQuery objects available in powershell and I'm also interested to know if there is a way to do that. See this and this question I created on that.

但我想出了这个技巧，在网页上运行javascript / jquery，并从PowerShell中的页面接收一些结果：

But I figured this trick to run javascript/jquery on the web page and receive some results back from the page in PowerShell:

# some web page with jQuery in it
$url = "http://jquery.com/"

# Use this function to run JavaScript on a web page. Your $jsCommand can
# return a value which will be returned by this function unless $global
# switch is specified in which case $jsCommand will be executed in global
# scope and cannot return a value. If you received error 80020101 it means
# you need to fix your JavaScript code.
Function ExecJavaScript($ie, $jsCommand, [switch]$global)
{
    if (!$global) {
        $jsCommand = "document.body.setAttribute('PSResult', (function(){$jsCommand})());"
    }
    $document = $ie.document
    $window = $document.parentWindow
    $window.execScript($jsCommand, 'javascript') | Out-Null
    if (!$global) {
        return $document.body.getAttribute('PSResult')
    }
}

Function CheckJQueryExists
{
    $result = ExecJavaScript $ie 'return window.hasOwnProperty("$");'
    return ($result -eq $true)
}

$ie = New-Object -COM InternetExplorer.Application -Property @{
    Navigate = $url
    Visible = $false
}
do { Start-Sleep -m 100 } while ( $ie.ReadyState -ne 4 )

$jQueryExists = CheckJQueryExists $ie
echo "jQuery exists? $jQueryExists"

# make a jQuery call
ExecJavaScript $ie @'
    // this is JS code, remember to use semicolons
    var content = $('#home-content');
    return content.text();
'@

# Quit and dispose IE COM
$ie.Quit()
[System.Runtime.Interopservices.Marshal]::ReleaseComObject($ie) | out-null
Remove-Variable ie

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