编译器生成的 Reference.vb 文件中的 Option Strict Off

Question

是什么原因导致 vb.net 编译器将 Option Strict Off 添加到为 asmx Web 引用创建的 Reference.vb 文件中？有时有有时没有，而且似乎从来都没有必要。

Answer 1

由于该文件有一个 header 与此类似（您的版本号可能不同）：

'------------------------------------------------------------------------------
' <auto-generated>
'     This code was generated by a tool.
'     Runtime Version:4.0.30319.42000
'
'     Changes to this file may cause incorrect behavior and will be lost if
'     the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------

第一个语句是：

Option Strict Off
Option Explicit On

我会说生成文件的工具正在使用 VBCodeProvider Class to produce the code using the CodeCompileUnit Class 并且该工具的作者没有覆盖 UserData 项目 AllowLateBound 和 RequireVariableDeclaration.

使用Reflector得到的Microsoft.VisualBasic.VBCodeGenerator.GenerateCompileUnitStart方法代码如下

Protected Overrides Sub GenerateCompileUnitStart(ByVal e As CodeCompileUnit)
    MyBase.GenerateCompileUnitStart(e)
    MyBase.Output.WriteLine("'------------------------------------------------------------------------------")
    MyBase.Output.Write("' <")
    MyBase.Output.WriteLine(SR.GetString("AutoGen_Comment_Line1"))
    MyBase.Output.Write("'     ")
    MyBase.Output.WriteLine(SR.GetString("AutoGen_Comment_Line2"))
    MyBase.Output.Write("'     ")
    MyBase.Output.Write(SR.GetString("AutoGen_Comment_Line3"))
    MyBase.Output.WriteLine(Environment.Version.ToString)
    MyBase.Output.WriteLine("'")
    MyBase.Output.Write("'     ")
    MyBase.Output.WriteLine(SR.GetString("AutoGen_Comment_Line4"))
    MyBase.Output.Write("'     ")
    MyBase.Output.WriteLine(SR.GetString("AutoGen_Comment_Line5"))
    MyBase.Output.Write("' </")
    MyBase.Output.WriteLine(SR.GetString("AutoGen_Comment_Line1"))
    MyBase.Output.WriteLine("'------------------------------------------------------------------------------")
    MyBase.Output.WriteLine("")
    If Me.AllowLateBound(e) Then
        MyBase.Output.WriteLine("Option Strict Off")
    Else
        MyBase.Output.WriteLine("Option Strict On")
    End If
    If Not Me.RequireVariableDeclaration(e) Then
        MyBase.Output.WriteLine("Option Explicit Off")
    Else
        MyBase.Output.WriteLine("Option Explicit On")
    End If
    MyBase.Output.WriteLine()
End Sub

...

Protected Function AllowLateBound(ByVal e As CodeCompileUnit) As Boolean
   Dim obj2 As Object = e.UserData.Item("AllowLateBound")
   If ((Not obj2 Is Nothing) AndAlso TypeOf obj2 Is Boolean) Then
      Return CBool(obj2)
   End If
   Return True
End Function

Protected Function RequireVariableDeclaration(ByVal e As CodeCompileUnit) As Boolean
   Dim obj2 As Object = e.UserData.Item("RequireVariableDeclaration")
   If ((Not obj2 Is Nothing) AndAlso TypeOf obj2 Is Boolean) Then
      Return CBool(obj2)
   End If
   Return True
End Function

编译器生成的 Reference.vb 文件中的 Option Strict Off

Option Strict Off in compiler generated Reference.vb file

vb.net

asmx