<script language=JavaScript>
function tofloat(f,dec) {
if(dec<0) return "Error:dec<0!";
result=parseInt(f)+(dec==0?"":".");
f-=parseInt(f);
if(f==0)
for(i=0;i<dec;i++) result+='0';
else {
for(i=0;i<dec;i++) f*=10;
result+=parseInt(Math.round(f));
}
return result;
}
alert(tofloat(123456789.0100000,3))
</script>
function tofloat(f,dec) {
if(dec<0) return "Error:dec<0!";
result=parseInt(f)+(dec==0?"":".");
f-=parseInt(f);
if(f==0)
for(i=0;i<dec;i++) result+='0';
else {
for(i=0;i<dec;i++) f*=10;
result+=parseInt(Math.round(f));
}
return result;
}
alert(tofloat(123456789.0100000,3))
</script>
onclick="javascript:alert(commafy(parseFloat(123456789.0100000)));"> 就是parseFloat()转化成浮点型
num = num+"";
var re=/(-?\d+)(\d{3})/
while(re.test(num)){
num=num.replace(re,"$1,$2")
}
pos = num.indexOf(".")
if(pos>0){
str = num.split(".")
tt = str[1].split(",").join("")
num = str[0]+'.'+tt
}
return num;
}
document.write(str.replace(/(\d{3})(?=[^.])/ig,"$1,"));