Question

Currently i’m developing an web automation system using WebBrowser control and AxWebBrowser control in windows form. But i found out there are IHTMLInputElement with mshtml and HTMLInputElement which both of them can be implemented. After i googled, i found out there are no clear comparison between these two… can anyone tell me what’s the differences ?

Answer 1

Many COM objects exposed by mshtml have several interfaces like ISomething, ISomething2, ISomething3, etc. Those represent the members that were added through separate versions of the browser. The interop class that’s associated with those typically implements all those interfaces, but from my experience you often cannot cast objects retrieved through mshtml in the associated class type. You must explicitly cast it to the interface that implements the member you need.