send string to internet explorer

My program can send string to any text or doc application on focus
but I have problem to send string to Internet expolorer ,in case of some forum have textarea ClassName:Shell DocObject View(like this forum quickreply) which my program can sendkeys on it , but at some other forum i can't.
As i know, almost everything inside the browser named as Shell DocObject View with same handle.
The cursor of textarea will be diappeared while i clicking on my program button.So i can't send string on it,
sendmessage or postmessage APi also tried but same result!!
any one can help me to solve my problem![HIGHLIGHT="vb"]
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