为什么要使用多的PreApplicationStartMethodAttribute不遵守？ [英] Why multiple using of PreApplicationStartMethodAttribute isn't complied?

问题描述

System.Web.PreApplicationStartMethodAttribute定义为：

System.Web.PreApplicationStartMethodAttribute defined as:

[AttributeUsage(AttributeTargets.Assembly, AllowMultiple=true)]
public sealed class PreApplicationStartMethodAttribute : Attribute 
{}

即它允许多个使用（的AllowMultiple = TRUE）。
但是，如果我尝试添加了一些这个属性的用法我总成：

I.e. it allows multiple usage (AllowMultiple=true). But if I try to added several usages of this attribute to my assembly :

[assembly: PreApplicationStartMethod(typeof(MyType1), "Start")]
[assembly: PreApplicationStartMethod(typeof(MyType2), "Start")]

我收到编译器错误：结果
错误2重复'PreApplicationStartMethod'属性。

I get compiler error:
Error 2 Duplicate 'PreApplicationStartMethod' attribute

这是为什么

推荐答案

我怀疑你是在看的。NET 4.5版本，它被记录为具有的AllowMultiple = TRUE 。

I suspect you were looking at the .NET 4.5 version, which is documented as having AllowMultiple = True.

对于文档在.NET 4.0版本显示为的AllowMultiple = FALSE ：

[AttributeUsageAttribute(AttributeTargets.Assembly, AllowMultiple = false)]
public sealed class PreApplicationStartMethodAttribute : Attribute

所以，如果你的目标.NET 4.5，它应该没问题。

So if you target .NET 4.5, it should be okay.

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