Using .Net Web Control - How to Set a Value in a TextBox *INSIDE* of an IFRAME.

Question

I'm trying to use a .Net WebBrowser control to log into a website and aggregate some data for me. I'm also using a reference to MSHTML (but I don't care if your solution does or doesn't).

When I visit a 'normal' website - I create an mshtml.HTMLDocument from the webBrowser's .documment. Then I create a mshtml.FormElement and a mshtml.HTMLInputElement using the name of the textbox I want.

Then, I can set the value of the textBox.

It looks something like this:

    Dim myDoc1 As mshtml.HTMLIFrame = DirectCast(Me.WebBrowser.Document.DomDocument, mshtml.HTMLDocument)
    Dim myForm As mshtml.HTMLFormElement = DirectCast(myDoc1.forms.item(0), mshtml.HTMLFormElement)
    Dim myUserBox As mshtml.HTMLInputElement = DirectCast(myForm.item("user"), mshtml.HTMLFormElement)

    myUserBox.value = UserName

My problem is that on some websites the textbox I need to manipulate is contained inside of an IFRAME. An example would be https://servicing.capitalone.com/c1/login.aspx

If my program surfs to that site - it can't find a textbox for the Username - because there isn't one. There is only an IFRAME tag that has a URL of 'https://login.capitalone.com/loginweb/login/login.do'

If I surf directly to the login.do page - the website redirects me to an error page.

How can I enter data into the UserName textbox in that IFRAME?

Answer 1

Because the child iframe you are trying to access is coming from a different domain than the parent page, you won't be able to access the form elements of the iframe due to cross-frame scripting security. See: Accessing Frames in the Managed HTML Document Object Model

Access to frames is complicated by the fact that the managed HTML DOM implements a security measure known as cross-frame scripting security. If a document contains a FRAMESET with two or more FRAMEs in different domains, these FRAMEs cannot interact with one another. In other words, a FRAME that displays content from your Web site cannot access information in a FRAME that hosts a third-party site such as http://www.adatum.com/. This security is implemented at the level of the HtmlWindow class. You can obtain general information about a FRAME hosting another Web site, such as its URL, but you will be unable to access its Document or change the size or location of its hosting FRAME or IFRAME.