如何在运行时为不同的角色和成员资格提供程序编辑app.config

Question

我正在开发Visual Studio 2015中的vb.net开发项目，并且需要能够在运行时编辑项目的app.config，以便访问不同网站的角色和成员资格提供程序。我希望能够更改 connectionStrings 部分中的 ApplicationServices 设置以及成员资格和角色管理器提供程序中的 applicationName 设置/ strong>部分。我已经编辑了项目基本目录中的初始 app.config 文件，如下所示：

    <?xml version="1.0" encoding="utf-8"?>
    <configuration>
      <startup>
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
      </startup>
      <connectionStrings>
        <clear />
        <add name="ApplicationServices" connectionString="Data Source=.\SQLEXPRESS; Integrated Security=True; User Instance=False; Connect Timeout=30; Initial Catalog=MYWEBSITE" providerName="System.Data.SqlClient" />
      </connectionStrings>
      <system.web>
        <membership>
          <providers>
            <clear />
            <add name="AspNetSqlMembershipProvider" type="System.Web.Security.SqlMembershipProvider" connectionStringName="ApplicationServices" applicationName="/" passwordFormat="Encrypted" enablePasswordRetrieval="true" enablePasswordReset="true" requiresQuestionAndAnswer="true" requiresUniqueEmail="true" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="8" minRequiredNonalphanumericCharacters="1" passwordAttemptWindow="5" />
          </providers>
        </membership>
        <roleManager enabled="true">
          <providers>
            <clear />
            <add name="AspNetSqlRoleProvider" type="System.Web.Security.SqlRoleProvider" connectionStringName="ApplicationServices" applicationName="/" />
            <add name="AspNetWindowsTokenRoleProvider" type="System.Web.Security.WindowsTokenRoleProvider" applicationName="/" />
          </providers>
        </roleManager>
      </system.web>
    </configuration>

在运行时，我尝试使用以下代码从上面显示的项目 app.config 文件中获取设置：

            Public Shared Function ReadAllConfigSettings(ByRef Configs(,) As String) As Boolean
        ReadAllConfigSettings = False
        Configs.Initialize()
        Dim ConfigCounter As Integer = 0
        Dim config As System.Configuration.Configuration = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)
        Try
            Dim Settings = config.AppSettings.Settings
            If Settings.Count = 0 Then
                ReadAllConfigSettings = False
                Exit Function
            Else
                For Each key As String In Settings.AllKeys
                    ConfigCounter = ConfigCounter + 1
                    Configs(ConfigCounter, 1) = key
                    Configs(ConfigCounter, 2) = Settings(key).Value
                Next
                ReadAllConfigSettings = True
            End If
        Catch e As ConfigurationErrorsException
            ReadAllConfigSettings = False
        End Try
    End Function

当我运行上面的代码时，从设置= config.AppSettings.Settings 代码行检索到的设置集合始终为空且带有空条目且 Settings.Count 为0。

我很难过为什么我没有将这个设置添加到 app.config 文件中，如果我甚至无法弄清楚如何更改它们，我就无法继续检索它们。有人能指出我正确的方向吗？

谢谢！

大卫

Answer 1

在重新思考这个过程之后，我想出了一个解决方案，似乎是一种不用尝试编辑 app.config 文件的方法。下面是我在研究问题时发现的片段中拼写的代码：

            Public Shared Function UpdateMembership(ConnectionStr As String, AppName As String, UserName As String, OldPassword As String, NewPassword As String, TheQuestion As String, TheAnswer As String, Optional TheError As String = Nothing) As Boolean
        UpdateMembership = False
        Dim IsMember As Boolean = False
        Dim AUser As MembershipUser
        Dim ChangePassOK As Boolean = False
        Dim ChangeQAOK As Boolean = False
        Try
            Dim settings As Object = ConfigurationManager.ConnectionStrings("ApplicationServices")
            Dim fi As Object = GetType(ConfigurationElement).GetField("_bReadOnly", (BindingFlags.Instance Or BindingFlags.NonPublic))
            fi.SetValue(settings, False)
            settings.ConnectionString = ConnectionStr
            Membership.Providers.Item("AspNetSqlMembershipProvider").ApplicationName = AppName
            Roles.Providers.Item("AspNetSqlRoleProvider").ApplicationName = AppName
            Roles.Providers.Item("AspNetWindowsTokenRoleProvider").ApplicationName = AppName
            IsMember = Membership.ValidateUser(UserName, OldPassword)
            If IsMember Then
                AUser = Membership.GetUser(UserName, False)
                If Not IsNothing(AUser) Then
                    ChangePassOK = AUser.ChangePassword(OldPassword, NewPassword)
                    If ChangePassOK Then
                        ChangeQAOK = AUser.ChangePasswordQuestionAndAnswer(NewPassword, TheQuestion, TheAnswer)
                    End If
                    If ChangeQAOK Then
                        UpdateMembership = True
                    End If
                End If
            End If
        Catch ex As Exception
            If Not IsNothing(TheError) Then
                TheError = ex.Message
            End If
        End Try
    End Function

它工作正常，因此可用于调整特定于每个站点配置的任何用户的安全设置。