在 IE 中执行 javascript 时遇到问题

Question

我在 vba 中创建了一个脚本，使用 IE 来单击网页中的选项卡。我想知道如何使用 .execScript.

在该选项卡上发起点击

当我像下面这样尝试时，它起作用了（不是理想的方法）：

Sub ExecuteScript()
    Dim IE As New InternetExplorer, Html As HTMLDocument

    With IE
        .Visible = True
        .navigate "https://whosebug.com/questions/tagged/web-scraping"
        While .Busy Or .readyState < 4: DoEvents: Wend
        Set Html = .document
        Html.parentWindow.execScript "document.querySelector(""a[href='/questions/ask']"").click();"
    End With
End Sub

我想做的方式如下，这样我就可以使用对象变量（相邻或内部）.execScript:

Set post = Html.querySelector("a[href='/questions/ask']")
Html.parentWindow.execScript "arguments[0].click();", post

但是，它会抛出指向这一行的错误 Html.parentWindow.execScript

Run-time error `429`
ActiveX component can't create object

如何在IE中执行javascript？

Answer 1

为什么不更改变量类型，以便您可以将 post 作为字符串（即选择器）传递。然后你可以连接进去。

Option Explicit
Public Sub ExecuteAScript()
    Dim IE As New InternetExplorer, Html As HTMLDocument, post As String, item As Object
    post = "a[href='/questions/ask']"

    With IE
        .Visible = True
        .navigate "https://whosebug.com/questions/tagged/web-scraping"
        While .Busy Or .readyState < 4: DoEvents: Wend
        Set Html = .document
        Do
            On Error Resume Next
            Set item = .document.querySelector("" & post & "")
            On Error GoTo 0
        Loop While item Is Nothing

        If Not item Is Nothing Then item.Click

        Stop
    End With
End Sub

如果你必须使用 execScript 我认为你不能像使用 selenium 那样使用 javascript return 调用传回值。您可以使用 js 向页面添加一个值，然后读回该值以便 return:

Option Explicit
Public Sub ExecuteAScript()
    Dim IE As New InternetExplorer
    post = "a[href='/questions/ask']"

    With IE
        .Visible = True
        .navigate "https://whosebug.com/questions/tagged/web-scraping"
        While .Busy Or .readyState < 4: DoEvents: Wend
        Do
            Call .document.parentWindow.execScript("document.title = document.querySelectorAll(" & Chr$(34) & post & Chr$(34) & ").length;")
        Loop While .document.Title = 0
        If IsNumeric(.document.Title) And .document.Title > 0 Then Debug.Print "Success"
    End With
End Sub

在 IE 中执行 javascript 时遇到问题

Trouble executing javascript within IE

vba

web-scraping

internet-explorer-11