js Math Date 字符串操作

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            document.write("s:"+s+"
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            document.write("s.length:"+s.length+"
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            document.write("s.charAt():"+s.charAt(5)+"
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            document.write("s.indexOf():"+s.indexOf(‘c‘)+"
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            document.write("s.lastIndexOf():"+s.lastIndexOf(‘c‘)+"
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            document.write("s.substring(1,3):"+s.substring(1,3)+"
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            document.write("s.substr(1,3):"+s.substr(1,3)+"
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            document.write("s.toUpperCase():"+s.toUpperCase()+"
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            document.write("s.split():"+s.split(‘k‘)+"
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            document.write("s.replace():"+s.replace("\\d","-")+"
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            document.write("s.match():"+s.match("\\d")+"
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            document.write("s.search():"+s.search("\\d")+"
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            document.write("--------------Date--------------------
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            var date = new Date();
            document.write("当前时间为:"+date+"
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            document.write("当前时间距1970.01.01.00:00:00的毫秒值 :"+date.getTime()+"
");//距1970.01.01.00:00:00的毫秒值 
            document.write("当前年为:"+date.getFullYear()+"
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            document.write("当前月为:"+date.getMonth()+1+"
")//月
            document.write("当前日为:"+date.getDay()+"
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            document.write("当前该月的第几天:"+date.getDate()+"
")//该月中某天 
            document.write("小时为:"+date.getHours()+"
")//小时数
            document.write("分钟为:"+date.getMinutes()+"
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            document.write("毫秒为:"+date.getMilliseconds()+"
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            document.write("当前日期为:"+date.toLocaleString()+"
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            document.write("--------------Math--------------------
")
            document.write("最大值为:"+Math.max(5,50,2.5,100.2)+"
")//最大值
            document.write("最小值为:"+Math.min(5,50,2.5,100.2)+"
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            document.write("绝对值为:"+Math.abs(-100)+"
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            document.write("四舍五入为:"+Math.round(2.6)+"
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            document.write("随机数为:"+Math.random()+"
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            document.write("小于指定值的最大整数为:"+Math.floor(2.5)+"
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            document.write("大于指定值的最小整数为:"+Math.ceil(2.5)+"
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