c# - 十进制。解析字符串，后缀为减号

Question

decimal decimalVal;
Decimal.TryParse("123-", out decimalVal);
Console.WriteLine(decimalVal); // -123

为什么“123-”字符串要这样解析？

Answer 1

Decimal.TryParse Method用 NumberStyles.Number 解析输入默认。 NumberStyles.Number包括 NumberStyles.AllowTrailingSign .

Decimal.TryParse Method (String, Decimal)

[...]
Parameter s is interpreted using the NumberStyles.Number style.
[...]

Number  Indicates that the AllowLeadingWhite, AllowTrailingWhite, AllowLeadingSign, AllowTrailingSign, AllowDecimalPoint, and AllowThousands styles are used. This is a composite number style.

AllowTrailingSign  Indicates that the numeric string can have a trailing sign. Valid trailing sign characters are determined by the NumberFormatInfo.PositiveSign and NumberFormatInfo.NegativeSign properties.