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var a =0;if (a) {alert (' true ')}, cannot bounce something because if (0) =if (false), so it is not executed directly

Source: Internet
Author: User
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1 <!DOCTYPE HTML>2 <HTML>3 <Head>4 <Metahttp-equiv= "Content-type"content= "text/html; charset=utf-8">5 <title>Untitled Document</title>6 <Script>7     vara=0;8     9     if(a) {Ten Alert ('I really do.')     One     } A </Script> - </Head> -  the <Body> - </Body> - </HTML>

If the condition followed by the IF is a Boolean value, True and False (false), and the Boolean value is False, there is a a=0;a=undifine;a=none in the case; A=nan;a=null five cases,

If after the if is false, then does not execute the function, so long will not eject anything

var a =0;if (a) {alert (' true ')}, cannot bounce something because if (0) =if (false), so it is not executed directly

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Related Keywords:
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