Invalid cast (mshtml.IHTMLInputImage)

[nara]

Hello

I have a problem with this code :
It throw the "System.InvalidCastException" exception.

I use mshtml.dll.

SomeOne could explain me why ?

For advance thanks...

JP

Message="Unable to cast COM object of type
'mshtml.HTMLInputElementClass' to interface type
'mshtml.IHTMLInputImage'. This operation failed because the
QueryInterface call on the COM component for the interface with IID
'{3050F2C2-98B5-11CF-BB82-00AA00BDCE0B}' failed due to the following
error: Cette interface n'est pas prise en charge (Exception from
HRESULT: 0x80004002 (E_NOINTERFACE))."
Source="Microsoft.mshtml"

{
webBrowser1.Navigate("http://www.google.com");
while ((webBrowser1.IsBusy) || (webBrowser1.ReadyState !=
WebBrowserReadyState.Complete))
{ Application.DoEvents(); };
for (int j = 0; j <= webBrowser1.Document.All.Count - 1; j++)
{
object obj;
mshtml.IHTMLInputImage intf;
obj = webBrowser1.Document.All[j].DomElement;

if (obj is mshtml.IHTMLInputImage)
{

intf = (obj as mshtml.IHTMLInputImage);
Debug.Assert(intf!=null);

MessageBox.Show(intf.name); // <-- This throw an exception
}
}

}