+1  A: 

To put string into the pasteboard, use

[UIPasteboard generalPasteboard].string = @"some text";

To get selected text from the WebView, use -stringByEvaluatingJavaScriptFromString: with appropriate Javascript.

KennyTM
You are "my God" ^0^.I see briliant light in your answer. i will checking now~~~Thank you so so so very much. (i have suffer from this problem while 5 days)ps. please pardon me my poor english. (i'm korean)
bluej3