Question

如何从this website抓取验证码 captchaImage。

我尝试了MSHTML，但是这个网站使用java脚本函数在它的src中显示检索验证码。请尝试回答我如何实现这一目标。

Imports MahApps.Metro.Controls
Imports System.Net
Imports System.Windows.Forms


Class MainWindow
    Inherits MetroWindow

    Private Sub MetroWindow_Loaded(sender As Object, e As RoutedEventArgs)
        wb.Navigate("https://www.irctc.co.in/eticketing/loginHome.jsf")
        AddHandler wb.LoadCompleted, AddressOf wb_Loaded
    End Sub
    Private Sub btngo_Click(sender As Object, e As RoutedEventArgs) Handles btngo.Click
        Dim htmldoc As MSHTML.IHTMLDocument2 = wb.Document
        Dim usrtxtdoc As MSHTML.IHTMLElement = htmldoc.all.item("j_username", 0)
        Dim usrpwddoc As MSHTML.IHTMLElement = htmldoc.all.item("j_password", 0)
        Dim captchadoc As MSHTML.IHTMLElement = htmldoc.all.item("j_captcha", 0)
        usrtxtdoc.innerText = txtusrname.Text
        usrpwddoc.innerText = txtpwd.Text
        captchadoc.innerText = txtcaptcha.Text
    End Sub

    Private Sub wb_Loaded(sender As Object, e As System.Windows.Navigation.NavigationEventArgs)
        MsgBox("Loaded")
        Dim htmldoc As MSHTML.IHTMLDocument2 = wb.Document
        Dim htmldoc2 As MSHTML.HTMLDocument = wb.Document
        Dim captchaimg As MSHTML.HTMLImg = htmldoc.all.item("cimage", 0)
        Dim bitmap As New BitmapImage
        bitmap.BeginInit()
        bitmap.UriSource = New Uri(wb.FindResource("captchaImage"))
        bitmap.EndInit()
        imgcaptcha.Source = bitmap
    End Sub

    Private Sub wb_Navigated(sender As Object, e As NavigationEventArgs) Handles wb.Navigated
        lblwbstatus.Content = "Load Completed"
    End Sub

    Private Sub wb_Navigating(sender As Object, e As NavigatingCancelEventArgs) Handles wb.Navigating
        lblwbstatus.Content = "Navigating Please wait"
    End Sub

    Private Sub lblwbstatus_MouseDoubleClick(sender As Object, e As MouseButtonEventArgs) Handles lblwbstatus.MouseDoubleClick
        wb.Refresh()
    End Sub
End Class

您可以从this link

下载来源

Answer 1

通常你会这样做：

sorted(temp_dict.items(), key=lambda x: int(x[1]))

然而，由于互联网资源管理器问题，图片有一个不会被复制到剪贴板的Alpha通道（正如您在此处阅读Copying image from page results in black image）。

其他方法是检查Internet Explorer缓存，但由于HTTP标头，该图像不会被缓存，因此您运气不佳。

Answer 2

上面的代码在考虑以下方面非常有效： 1-项目类型-如您的网页目标示例（“ IMG”）中所述。 2-图像专有名称示例：CaptchaImg.jpg被写为CaptchaImg.jpg 3-添加对（mshtml）的引用并将mshtml导入您的项目 4-右键单击您项目上的引用->单击添加引用-> ->浏览按钮单击-选择或导航到---> C：\ Windows \ assembly \ GAC \ Microsoft.mshtml \ 7.0.3300.0__b03f5f7f11d50a3a \ Microsoft.mshtml.dll ---->单击确定按钮---这会将Microsoft.mshtml.dll添加到您的引用中将finallt导入为项目（导入mshtml）。 5-将目录bmp.Save（“ c：\ test.bmp”）--->更改为例如bmp.Save（“ c：\ test \ test.bmp”）享有安全和管理权。

如果src使用java函数，如何获取验证码图像？

2 个答案: