Force plaintext copy from a Cocoa WebView

I开发者_JS百科 have a Cocoa Webview subclass, and I need to make all text copied from it be plaintext only. I have tried overriding -copy and -pasteboardTypesForSelection, but no luck, and debugging code seems to indicate that those methods are never called. I've also tried setting -webkit-user-modify to read-write-plaintext-only in the css (this would also work in this situation) but that seemed to have no effect.

Any ideas?

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Okay this seems to work (with the subclass instance as its own editing delegate):

- (BOOL)webView:(WebView *)webView doCommandBySelector:(SEL)command
{
    if (command == @selector(copy:)) {
        NSString *markup = [[self selectedDOMRange] markupString];
        NSData *data = [markup dataUsingEncoding: NSUTF8StringEncoding];
        NSNumber *n = [NSNumber numberWithUnsignedInteger: NSUTF8StringEncoding];
        NSDictionary *options = [NSDictionary dictionaryWithObject:n forKey: NSCharacterEncodingDocumentOption];
        NSAttributedString *as = [[NSAttributedString alloc] initWithHTML:data options:options documentAttributes: NULL];
        NSString *selectedString = [as string];
        [as autorelease];

        NSPasteboard *pasteboard = [NSPasteboard generalPasteboard];
        [pasteboard clearContents];
        NSArray *objectsToCopy = [NSArray arrayWithObject: selectedString];
        [pasteboard writeObjects:objectsToCopy];
        return YES;
    }
    return NO;
}

Not sure if this is the best way.