powershell - 在HTML页面中单击<按钮>

Question

<button type="submit">Login</button>

我正在尝试使用Windows Powershell单击/提交上述按钮。我尝试了以下代码:

$submitButton = $doc.documentElement.getElementsByClassName('button') |
                Select-Object -First 1
$submitButton.click()

这会带来此错误:

You cannot call a method on a null-valued expression.ps1:15 char:1+     $submitButton = $doc.documentElement.getElementsByClassName('button') | ...+     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException    + FullyQualifiedErrorId : InvokeMethodOnNullYou cannot call a method on a null-valued expression.ps1:16 char:1+ $submitButton.click()+ ~~~~~~~~~~~~~~~~~~~~~    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException    + FullyQualifiedErrorId : InvokeMethodOnNull

I also tried this code:

$loginBtn = $ie.Document.getElementsById('input') |
            Where-Object {$_.Type -eq 'button' -and $_.Value -eq 'LoginButton'}
$loginBtn.click()

但这也会带来与以前相同的错误。

我的PowerShell代码完整:

$username='USERNAME' 
$password='PASSWORD'

$ie = New-Object -ComObject 'internetExplorer.Application'
$ie.Visible= $true
$ie.Navigate("URL EXAMPLE")

while ($ie.Busy -eq $true){Start-Sleep -seconds 1;}   

$Open = $ie.Document.getElementByID('has-account')
$Open.click()

$usernamefield = $ie.Document.getElementByID('login-usr').value =          $username
$passwordfield = $ie.Document.getElementByID('login-pass').value =     $password
$submitButton = $doc.documentElement.getElementsByClassName('button') |     Select-Object -First 2
$submitButton.click() 

编辑

这是powershell getelementbytagname的输出。注意没有类名或ID，如何单击它？

className                    : 
id                           : 
tagName                      : BUTTON
parentElement                : System.__ComObject
style                        : System.__ComObject
document                     : mshtml.HTMLDocumentClass
sourceIndex                  : 60
offsetLeft                   : 61
offsetTop                    : 220
offsetWidth                  : 320
offsetHeight                 : 41
offsetParent                 : System.__ComObject
innerHTML                    : Login
innerText                    : Login
outerHTML                    : <button type="submit">Login</button>
outerText                    : Login
parentTextEdit               : System.__ComObject

编辑

<form id="sp-login-form" action="#" method="post">
        <button type="button" id="fb-login-btn" class="button fb">Log in with Facebook<span style="position: absolute;"></span></button>
        <em>or</em>
        <div>
          <label for="login-usr">Username</label>
          <input type="text" name="username" id="login-usr" placeholder="Spotify username">
          <label for="login-pass" class="pass">Password</label>
          <input type="password" name="password" id="login-pass" class="pass" placeholder="Password">
          <button type="submit">Login</button>
        </div>
      </form>

Answer 1

在您共享的代码中，$doc变量未初始化。请在下面的行中使用首先对其进行初始化:

$doc.documentElement.getElementsByClassName('button')

此行的错误，即null-valued expression错误，是由于$doc在这一点上为空。

替代解决方案:而是尝试以下代码来获取页面上表单中的“提交”按钮。您可以根据需要和目标页面来调整代码。

$submitButton=$ie.Document.getElementsByTagName("button") | Where-Object {$_.innerhtml -eq 'Login'}
$submitButton.click();