■スクリプト
<HTML> <HEAD> <TITLE>Sample</TITLE> </HEAD> <SCRIPT Language="JavaScript"> <!-- newWin = window.open("Dummy.htm","Sample","width=200,height=200"); // --> </SCRIPT> <BODY bgColor="white"> <FORM> <INPUT TYPE="button" VALUE="クローズチェック" onCLick="alert(newWin.closed)"> </FORM> </BODY></HTML>