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?????? BOM ??

BOM??

  • BOM? Browser Object Model? ???, Browser Object Model???? ???

  • BOM? ???? ????? ???? ?? ?????? ??? ?????

  • BOM? ?? ? ?? ??? ???? ? ????? ? ?? ??? ????

  • BOM? ??? ?? ??? ???? ? ??? ??? ???? ??? ?????.

  • BOM?? JavaScript ??? ?? ??? ??? ?????. ECMA?? DOM ??? ??? W3C???

  • BOM? ?? Netscape ???? ??? ??????

? ??? ?? ??

? ??????? ???? ?? ??? ????. ????? ??? ???? ??? ? ?? ??? ??, ?????? ??? ? ?? ?? ??? ???? ??, ????? ????, ??? ?? ??? ?? ? ?? ?????? ?? ?? ?? ???, ??? HTML ??? ?? ???

BOM ?? ?????

?? ??? ? ????.

6.png

??: ? ??? BOM? ???(??) ???? ?? ??? ?? ?? ?????. window


window? ??? ????? ?? ??? ??? ? ? ??? ???? ?? ??? ? ????. ?? ?? ?? ? ????. ?? ?? ?????: 

<!DOCTYPE HTML>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
        <title>php.cn</title>
        <script>
            window.alert("Hello JavaScript");
            alert("Hello JavaScript");
        </script>
    </head>
    <body>
    </body>
</html>


???? ??
||
<!DOCTYPE HTML> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>php.cn</title> <script> window.alert("Hello JavaScript"); alert("Hello JavaScript"); </script> </head> <body> </body> </html>