Question

我正在努力做到这一点，因此我可以在表单中有几个文本框来显示特定网页上的信息。例如，是否可以通过单击Visual Basic中的按钮将这个问题的标题检索为变量？

Answer 1

这并不难，但是您必须查看源页面并识别元素。

在结构良好的页面中，通常div元素具有标签ID，但通常没有标签ID，因此您必须使用属性名称来抓住它-通常您可以使用所涉及的div的类名。

那么，要获取标题，您是否对这篇文章的文本有所疑问？

这有效：

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

    Dim xDoc As New Xml.XmlDocument

    Dim strURL As String = "https://stackoverflow.com/questions/55753982"

    Dim xWeb As New WebBrowser

    xWeb.ScriptErrorsSuppressed = True
    xWeb.Navigate(strURL)
    Do Until xWeb.ReadyState = WebBrowserReadyState.Complete
        Application.DoEvents()
    Loop

    Dim HDoc As HtmlDocument = xWeb.Document

    Debug.Print(HDoc.GetElementById("question-header").FirstChild.InnerText)
    Debug.Print(FindClass(HDoc, "post-text"))

End Sub

Function FindClass(Hdoc As HtmlDocument, strClass As String) As String

    ' get all Divs, and search by class name
    Dim OneElement As HtmlElement
    For Each OneElement In Hdoc.GetElementsByTagName("div")
        If OneElement.GetAttribute("classname") = strClass Then
            Return OneElement.InnerText
        End If
    Next
    ' we get here, not found, so return a empty stirng
    Return "not found"

End Function

输出：

（第一部分是标题问题）

Is there a way to retrieve some text from a webpage to a textbox in VB?

（第二部分是问题文本）

I'm trying to make it so I can have several text boxes in my form show pieces of
information from a specific webpage. For example, would there be a way I would be
able to retrieve the title of this question to a variable with the click of a button
in Visual Basic?

有没有一种方法可以将网页中的某些文本检索到VB中的文本框？

1 个答案: