/**  * 格式化数字显示方式   * 用法  * formatNumber(12345.999,'#,##0.00');  * formatNumber(12345.999,'#,##0.##');  * formatNumber(123,'000000');  * @param num  * @param pattern  */  function formatNumber(num,pattern){    var strarr = num?num.toString().split('.'):['0'];    var fmtarr = pattern?pattern.split('.'):[''];    var retstr='';      // 整数部分    var str = strarr[0];    var fmt = fmtarr[0];    var i = str.length-1;      var comma = false;    for(var f=fmt.length-1;f>=0;f--){      switch(fmt.substr(f,1)){        case '#':          if(i>=0 ) retstr = str.substr(i--,1) + retstr;          break;        case '0':          if(i>=0) retstr = str.substr(i--,1) + retstr;          else retstr = '0' + retstr;          break;        case ',':          comma = true;          retstr=','+retstr;          break;      }    }    if(i>=0){      if(comma){        var l = str.length;        for(;i>=0;i--){          retstr = str.substr(i,1) + retstr;          if(i>0 && ((l-i)%3)==0) retstr = ',' + retstr;         }      }      else retstr = str.substr(0,i+1) + retstr;    }      retstr = retstr+'.';    // 处理小数部分    str=strarr.length>1?strarr[1]:'';    fmt=fmtarr.length>1?fmtarr[1]:'';    i=0;    for(var f=0;f