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JavaScript ?? ??

TBoolean ??? ??? ?? ?? ?? ?(true ?? false)?? ???? ? ?????.

?? ?? ???

?? ??? "true" ?? "false"?? ? ?? ?? ?????.

?? ??? myBoolean??? ?? ??? ?????.

var myBoolean=new Boolean();

If Boolean ??? ??? ????. ?? ?? ??? ?? ?? ??? ????.

0-0null""falseundefineNaN

??? ??? ?? false???. ??? ??? ?? ?? true???(??? ??? "false"? ????).


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<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>php中文網(wǎng)(php.cn)</title> </head> <body> <script> var b1=new Boolean(0); var b2=new Boolean(1); var b3=new Boolean(""); var b4=new Boolean(null); var b5=new Boolean(NaN); var b6=new Boolean("false"); document.write("0 為布爾值 "+ b1 +"<br>"); document.write("1 為布爾值 "+ b2 +"<br>"); document.write("空字符串是布爾值 "+ b3 + "<br>"); document.write("null 是布爾值 "+ b4+ "<br>"); document.write("NaN 是布爾值 "+ b5 +"<br>"); document.write("字符串'false' 是布爾值"+ b6 +"<br>"); </script> </body> </html>