vb.net - Option Strict On 不允许缩小方法和委托之间的隐式类型转换

Question

错误：Option Strict On 不允许缩小方法'context_beginRequest<ByVal sender As Object, ByVal e As WindowsAuthenticationEventArgs>'和委托之间的隐式类型转换'<BeginRequest>'

对于代码：

Public Sub Init(ByVal context As System.Web.HttpApplication) Implements System.Web.IHttpModule.Init
    'context.
    AddHandler context.BeginRequest, New EventHandler(AddressOf context_BeginRequest)
End Sub

context_BeginRequest 函数::

Public Sub context_BeginRequest(ByVal sender As Object, ByVal e As WindowsAuthenticationEventArgs)
.....

.....结束子

Answer 1

那是因为HttpApplication.BeginRequestis just of type EventHandler... 所以你的第二个参数应该是 type EventArgs，而不是WindowsAuthenticationEventArgs。