blocks|key|1099369|text|我认为这是不可能的，因为出于某种原因，它已经被明确禁止用于过时属性。根据围绕属性目标定义的规则，似乎没有任何理由使过时的属性在属性get或set访问器上无效。若要将属性应用于特性集访问器，请使用that+attribute+must+be+applicable+to+either+a+method,+parameter,+or+return+value+target。如果查看the+Obsolete+attribute，您可以看到"method“是该属性的有效目标之一。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1099370|实际上，您可以使用与过时属性with+the+AttributeUsage+attribute相同的有效目标来定义自己的属性，并且您会发现可以将其应用于属性get或set访问器，而不能应用过时属性。|1099371|[AttributeUsage(AttributeTargets.Method)]
class+MyMethodAttribute+:+Attribute+{+}

class+MyClass
{
++++private+int+_Id;

++++public+int+Id
++++{
++++++++get+{+return+_Id;+}

++++++++[MyMethodAttribute]+//+this+works+because+"Method"+is+a+valid+target+for+this+attribute
++++++++[Obsolete]+//+this+does+not+work,+even+though+"Method"+is+a+valid+target+for+the+Obsolete+attribute
++++++++set+{+_Id+=+value;+}
++++}
}|code-block|syntax|javascript|1099372|如果您尝试创建在属性集访问器上无效的自己的属性，并将其应用于属性集访问器，则可能会注意到错误消息略有不同。自定义属性的错误消息将是“属性'YourCustomAttribute‘在此声明类型上无效。”，而过时属性的错误消息是“属性’过时‘在属性或事件访问器上无效”。错误消息不同的事实使我相信，无论出于何种原因，这是一条显式地内置于编译器中的过时属性的规则，而不是依赖于AttributeUsage属性，后者理应应用于过时属性。|1099373|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/b3787ac0%2528VS.80%2529.aspx|1|http://msdn.microsoft.com/en-us/library/system.obsoleteattribute.aspx|2|http://msdn.microsoft.com/en-us/library/tw5zxet9%2528VS.71%2529.aspx^0|2P|2F|0|59|M|1|0|E|X|2|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@$A|Z|B|10|1|11]|$A|12|B|13|1|14]]|C|$]]|$1|D|3|E|5|6|7|15|8|@]|9|@$A|16|B|17|1|18]]|C|$]]|$1|F|3|G|5|H|7|19|8|@]|9|@]|C|$I|J]]|$1|K|3|L|5|6|7|1A|8|@]|9|@]|C|$]]|$1|M|3|-4|5|6|7|1B|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]|U|$5|P|Q|R|C|$S|V]]|W|$5|P|Q|R|C|$S|X]]]]

I think that this can't be done because, for some reason, it has been specifically disallowed for the Obsolete attribute. According to the rules defined around attribute targets, there doesn't appear to be any reason that the Obsolete attribute would not be valid on a property get or set accessor. In order to apply an attribute to a property set accessor, <a href="http://msdn.microsoft.com/en-us/library/b3787ac0%28VS.80%29.aspx">that attribute must be applicable to either a method, parameter, or return value target</a>. If you look at <a href="http://msdn.microsoft.com/en-us/library/system.obsoleteattribute.aspx">the Obsolete attribute</a>, you can see that "method" is one of the valid targets for that attribute.

In fact, you can define your own attribute with the same valid targets as the Obsolete attribute <a href="http://msdn.microsoft.com/en-us/library/tw5zxet9%28VS.71%29.aspx">with the AttributeUsage attribute</a>, and you'll find that you can apply it to a property get or set accessor whereas you cannot apply the Obsolete attribute.

<pre><code>[AttributeUsage(AttributeTargets.Method)]
class MyMethodAttribute : Attribute { }

class MyClass
{
 private int _Id;

 public int Id
 {
 get { return _Id; }

 [MyMethodAttribute] // this works because "Method" is a valid target for this attribute
 [Obsolete] // this does not work, even though "Method" is a valid target for the Obsolete attribute
 set { _Id = value; }
 }
}
</code></pre>

If you try creating your own attribute that is not valid on a property set accessor and you apply it there, then you may notice the error message is slightly different. The error message for your custom attribute will be "Attribute 'YourCustomAttribute' is not valid on this declaration type.", whereas the error message for the Obsolete attribute is "Attribute 'Obsolete' is not valid on property or event accessors." The fact that the error message is different makes me believe that this is a rule that is, for whatever reason, explicitly built into the compiler for the Obsolete attribute, rather than relying on the AttributeUsage attribute that is, supposedly, applied to the Obsolete attribute.

blocks|key|884588|text|此功能现已包含在C#+8.0中。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|884589|感谢威利博士的学徒，他指出这与他的答案中的其他属性不一致，并激励我实现这一点。|884590|进行这些更改的PR在这里：https://github.com/dotnet/roslyn/pull/32571|offset|length|884591|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/dotnet/roslyn/pull/32571^0|0|0|D|17|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@$F|S|G|T|1|U]]|A|$]]|$1|H|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|O]]]]

The ability to do this has now been included in C# 8.0.

Thank you to Dr. Wily's Apprentice who pointed out this was inconsistent to other attributes in his answer, and inspired me to implement this.

The PR where these changes were made is here: <a href="https://github.com/dotnet/roslyn/pull/32571" rel="noreferrer">https://github.com/dotnet/roslyn/pull/32571</a>

Is it possible to use Obsolete attribute on only a getter or a setter of a property?

I would like to be able to do something like this:

<pre><code>public int Id {
 get { return _id;}
 [Obsolete("Going forward, this property is readonly",true)]
 set { _id = value;}
}
</code></pre>

but obviously that will not build. Is there a work around that allows me to apply this attribute to just the setter?

Is it possible to use Obsolete attribute on only a getter or a setter of a property

编译器

是否可以仅在属性的getter或setter上使用过时属性？我希望能够做这样的事情：public int Id {    get { return _id;}    [Obsolete("Going forward, this property is readonly",true)]    set { _id = va...

问是否可以仅在属性的getter或setter上使用过时属性
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