怎样得到任意选中的文本(只是选中，未复制到剪切板)(50分)

f1:=GetForegroundWindow;
f2:=GetWindowThreadProcessId(f1,nil);
AttachThreadInput(GetCurrentThreadId,f2,true);
f3:=getfocus;
AttachThreadInput(GetCurrentThreadId,f3,false);
Lbl.Caption := 'FocusWndHandle:' + inttostr(f3);

f1:=GetForegroundWindow;
f2:=GetWindowThreadProcessId(f1,nil);
AttachThreadInput(GetCurrentThreadId,f2,true);
f3:=getfocus;
AttachThreadInput(GetCurrentThreadId,f3,false);
Lbl.Caption := 'FocusWndHandle:' + inttostr(f3);

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