js floating point numbers retain two decimal points sample code (rounding)_javascript skills

Copy code The code is as follows:

var changeTwoDecimal_f= function (floatvar){
var f_x = parseFloat (floatvar);
if (isNaN(f_x)){
return '0.00';
}
var f_x = Math.round(f_x*100)/100;
var s_x = f_x.toString();
var pos_decimal = s_x.indexOf('.');
if (pos_decimal < 0){
pos_decimal = s_x.length;
s_x = '.';
}
while (s_x.length <= pos_decimal 2){
s_x = '0';
}
return s_x;
}

Rounding function provided by js:

Copy code The code is as follows:

js rounding function toFixed( ), the parameter inside is the number of decimal places to retain.

<script language="javascript">
document.write("<h1>JS example of retaining two decimal places</h1><br>");
var a=2.1512131231231321;
document.write("Original value:" a "<br>");
document.write("Two decimal points:" a.toFixed(2) "<br> Four decimal points" a.toFixed(4));
</script>