java保留小数点后两位数

[放假接口]

import java.math.BigDecimal;
import java.text.DecimalFormat;
import java.text.NumberFormat;
public class format {
    double f = 111231.5585;
    public void m1() {
        BigDecimal bg = new BigDecimal(f);
        double f1 = bg.setScale(2, BigDecimal.ROUND_HALF_UP).doubleValue();
        System.out.println(f1);
    }
    /**
     * DecimalFormat转换最简便
     */
    public void m2() {
        DecimalFormat df = new DecimalFormat("#.00");
        System.out.println(df.format(f));
    }
    /**
     * String.format打印最简便
     */
    public void m3() {
        System.out.println(String.format("%.2f", f));
    }
    public void m4() {
        NumberFormat nf = NumberFormat.getNumberInstance();
        nf.setMaximumFractionDigits(2);
        System.out.println(nf.format(f));
    }
    public static void main(String[] args) {
        format f = new format();
        f.m1();
        f.m2();
        f.m3();
        f.m4();
    }
}

[tony4geek]

[小博测试成长之路]

[最初最后]

用这个吧 DecimalFormat df = new DecimalFormat(".00"); .00就表示保留后两位数 然后df.format();就ok啦

[徐老半狼]

[KevinXC5]

param = (double)Math.round(param*100)/100 其实用这种方法也是可以实现的

[zfthinker]

DecimalFormat df = new DecimalFormat(".00");

[caewow]

[别闹腰不好]

public static Double roundDouble(double val, int precision) { Double ret = null; try { double factor = Math.pow(10, precision); //ret=Math.round(val*factor)/factor; ret = Math.floor(val * factor + 0.5) / factor; } catch (Exception e) { e.printStackTrace(); } return ret; }

[qinyifang123]

[a9744490]

(double)((int)num*100)/100 这样有啥损失没