在Java將double轉型BigDecimal注意事項
這篇介紹在Java將double轉型BigDecimal注意事項。
incorrect Example
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| float a = 57.3f;
BigDecimal decimalA = new BigDecimal(a);
System.out.println(decimalA);
Output:57.299999237060546875
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double b = 57.3;
BigDecimal decimalB = new BigDecimal(b);
System.out.println(decimalB);
Output:57.2999999999999971578290569595992565155029296875
結論:避免直接使用new BigDecimal(double) or new BigDecimal(float)
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correct Example
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| double c = 57.3;
BigDecimal decimalC = new BigDecimal(Double.toString(c));
System.out.println(decimalC);
Output:57.3
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double d = 57.3;
BigDecimal decimalD = BigDecimal.valueOf(d);
System.out.println(decimalD);
Output:57.3
結論:建議使用new BigDecimal(Double.toString(c)) and BigDecimal.valueOf(d)
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