问题是该属性的默认值 ColorEnum 不是你的枚举的有效值：当你创建一个为MyObject ，该属性的默认值是0，0不符合您的枚举的任意值。

The problem is the default value for the property ColorEnum is not a valid value for your enum: when your create a MyObject, the default value for the property is 0, and 0 does not correspond to any value of your enum.

您有多种选择来纠正这种行为。

You have multiple options to correct this behavior.

• 您可以红= 0 而不是红= 1 （甚至忽略它，它也有同样的效果）在枚举声明。这样的话，默认值将是红色的，而不是无意义的值。


• 您可以将默认值默认值= 0添加到您的枚举，你知道将有颜色的含义无法定义。


• 您可以有你的属性格式是一个可空颜色？，所以空将成为既是一个法律价值和默认为属性



• 您可以为MyObject 的构造函数指定默认颜色的ColorEnum属性。

• You can have Red = 0 instead of Red = 1 (or even omit it, it would have the same effect) in your enum declaration. That way, the default value would be Red instead of a nonsensical value.
• You can add a default value Default = 0 to your enum that you know will have the meaning of "the color has not be defined".
• You can have your propery be a nullable Color?, so null would become both a legal value and the default for the property

• You can have the constructor of MyObject assign a default color to the ColorEnum property.

公开为MyObject（）
{
this.ColorEnum = Color.Red;
}

public MyObject() { this.ColorEnum = Color.Red; }

但是，不管你做什么，一个枚举类型的defaul值将始终为0，如果0不对应于合法枚举构件，它必然是一个问题。

But whatever you do, the defaul value for an enumeration type will always be 0. if 0 does not correspond to a legal enum member, it's bound to be a problem.