java 使用 char 格式化字符串到小数点后两位

Question

这个问题已经有答案了:

Best way to Format a Double value to 2 Decimal places [duplicate] (2 个回答)

Limit a double to two decimal places [duplicate] (5 个回答)

已关闭 8 年前。

所以我在格式化字符串时遇到问题。

我的输出应该始终是 ##.##C or F (温度换算)

这是我的方法:

public void setResultLabel(double inNumber, char inChar)
{   

    String number, letter;

    number = String.valueOf(inNumber);

    letter = String.valueOf(inChar);

    String temp;

    temp = number + letter;

    String format = String.format("%2.5s", temp); /* how do you make this code 
    so that the out put result will always be up to two decimal places 
    with a char C or F? */

    result.setText(format);

    add(result);
}

Answer 1

public void setResultLabel(double inNumber, char inChar)
{   

    String number, letter;
    DecimalFormat decimalFormat = new DecimalFormat("##.##"+inChar);


    String formated = decimalFormat.format(inNumber); 
    /* formated  is your result  */
    // System.out.println(formated);

    result.setText(format);
    add(result);
}