java科学计数法转普通计数法字符串简易方法

java科学计数法转普通计数法字符串简易方法,不需要format;

String t = "2.0090102E9";
BigDecimal b = new BigDecimal(t);	
System.out.println(b.toPlainString()); 

输出：
2009010200

评论

2 楼 xunke515 2013-05-06  

挺好~,感谢

1 楼 modiliany 2012-04-09  

楼主没有试过大数值吧？位数大了，BigDecimal出误差

    double[] testData = {  
                    //测试数据一  
                    0,  
                    1,  
                    10,  
                    100,  
                    1000,  
                    10000,  
                    100000,  
                    1000000,  
                    10000000,  
                    100000000,  
                    1000000000,  
                    10000000000d,  
                    100000000000d,  
                    1000000000000d,  
                    10000000000000d,  
                    100000000000000d,  
                    1000000000000000d,  
                    10000000000000000d,  
                    100000000000000000d,  
                    //测试数据二  
                    110000000000000000d,  
                    101000000000000000d,  
                    100100000000000000d,  
                    100010000000000000d,  
                    100001000000000000d,  
                    100000100000000000d,  
                    100000010000000000d,  
                    100000001000000000d,  
                    100000000100000000d,  
                    100000000010000000d,  
                    100000000001000000d,  
                    100000000000100000d,  
                    100000000000010000d,  
                    100000000000001000d,  
                    100000000000000100d,  
                    100000000000000010d,  
                    100000000000000001d,  
                    //测试数据三  
                    101010101010101010d,  
                    100100100100100100d,  
                    100100010010001000d,  
                    100100001000010001d,  
                    100001000001000001d,  
                    100010000100010010d,  
                    111111111111111111d,  
                    123456789012345678d,  
                    //测试数据四  
                    1000000000000000000d  
            };  
      
      
      
//		String str = new BigDecimal(d).setScale(2, BigDecimal.ROUND_HALF_UP).toString();
		String str = new BigDecimal(d).setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString();

//		DecimalFormat format = new DecimalFormat();
//		format.applyPattern("#################0.00");
//		String str = format.format(d);
              
      
    //三种结果都是：  
    //100000000000001000 格式化之后是：  
    //100000000000000992