JAVA儲存兩位小數點的四種方法
阿新 • • 發佈：2019-02-20
import java.math.BigDecimal;
import java.text.DecimalFormat;
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轉換最簡便
System.out.println(df.format(f));
* String.format列印最簡便
}
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();
}
}
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轉換最簡便
*/
public void m2() {
DecimalFormat df = new DecimalFormat("#.00");System.out.println(df.format(f));
}
/*** String.format列印最簡便
*/
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();
}
}