关于.net：+ =运算符是否确保在C＃中进行EXPLICIT转换或隐式CASTING？

Does += operator ensures an EXPLICIT conversion or implicit CASTING in C#?

下面的示例编译：

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public static void Main()
{
Byte b = 255;
b += 100;

}

但下面这个失败了

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public static void Main()
{
Byte b = 255;
b = b + 100;
}

具有

Error 1 Cannot implicitly convert type 'int' to 'byte'. An explicit conversion exists (are you missing a cast?)

这是否意味着对于c+=运算符提供显式转换？

埃里克·利珀特很详细地回答了你的问题。

Another interesting aspect of the predefined compound operators is
that if necessary, a cast – an allegedly"explicit" conversion – is
inserted implicitly on your behalf. If you say

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short s = 123;
s += 10;

then that is not analyzed as s = s + 10 because short plus int is int,
so the assignment is bad. This is actually analyzed as

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s = (short)(s + 10);

so that if the result overflows a short, it is automatically cut back
down to size for you.

另见第二部分。