字符串.isemail()实现

String.prototype.isemail = function (){return /^[\w\d]([\w\d\.]*[\w\d])?@([\w\d\-]\.)+[a-z]{2,}$/.test(this);}

//说明:允许 -.com域名格式;
alert('[e-mail]'.isemail())

/*

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来自网页的消息
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true
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确定   
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*/


alert('dddd@d.o'.isemail())

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来自网页的消息
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false
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确定   
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