Float retains two decimal places

1. Page Operation formatting numbers

On the page sometimes use the number of operations, after the operation will appear 1.5999999999999 such a long number, need to format numbers, such as the retention of two valid digits

First import this label

<% @ taglib URI = " http://java.sun.com/jsp/jstl/fmt " prefix = " FMT " %>

Then use the label language

<type= "number"  value= "${cost-beannums}"  pattern = "0.00" maxfractiondigits = "2" />

2. Pass the value to the page before formatting the number

DecimalFormat decimalformat=New DecimalFormat ("#0.00"); // the character format of the constructed method here if the decimal place is less than 2 bits, it will be 0. String P=decimalformat.format (cost); // format returns a string

This time the value to the page is a string form, if the use of El expression, the following is wrong, because cost is a string form, can not compare size

<C:whenTest= "${beannums! = 0 && cost>beannums}"><spanclass= "Ml50 Pay_by_cash_span">￥<Fmt:formatnumbertype= "Number"value= "${cost-beannums}"pattern= "0.00"maxfractiondigits= "2"/></span></C:when>

So we need to do the math first.

<C:whenTest= "${beannums! = 0 && cost-beannums>0}"><spanclass= "Ml50 Pay_by_cash_span">￥<Fmt:formatnumbertype= "Number"value= "${cost-beannums}"pattern= "0.00"maxfractiondigits= "2"/></span></C:when>

Float retains two decimal places