VB.NET App.config 配置文件读写

使用示例:

Public Class Form1
    Public Sub New()
        InitializeComponent()
        AppConfig.Appconfig_init()
    End Sub
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        MsgBox(AppConfig.Insert_Config("bb", "89898", AppConfig.App_mode.app_config))
        'MsgBox(AppConfig.GET_Config("SQLiteDB", AppConfig.App_mode.connection_config))
    End Sub
End Class

''' <summary>
''' AppConfig节点配置
''' </summary>
Public Class AppConfig
    Public Shared Appfig As AppConfig = Nothing
    Private Shared ConFig As Object
    Private Shared App_set As Configuration.AppSettingsSection
    Private Shared App_connection As Configuration.ConnectionStringsSection

    ''' <summary>
    ''' 类型分配
    ''' </summary>
    Enum App_mode
        ''' <summary>
        ''' app配置
        ''' </summary>
        app_config = 1
        ''' <summary>
        ''' 连接配置
        ''' </summary>
        connection_config = 2
    End Enum

    Public Sub New()
    End Sub

    ''' <summary>
    ''' 初始化AppConfig
    ''' </summary>
    ''' <returns></returns>
    Public Shared Function Appconfig_init() As AppConfig
        Try
            ConFig = Configuration.ConfigurationManager.OpenExeConfiguration(Configuration.ConfigurationUserLevel.None)
            App_connection = ConFig.ConnectionStrings
            App_set = ConFig.AppSettings
            If Appfig Is Nothing Then Appfig = New AppConfig
            Return Appfig
        Catch ex As Exception
            Return Nothing
        End Try
    End Function

    ''' <summary>
    ''' 读取app.config节点值
    ''' </summary>
    ''' <param name="KEYSTR"></param>
    ''' <returns></returns>
    Public Shared Function GET_Config(ByVal KEYSTR As String, ByVal mode As App_mode) As String
        Try
            Dim Temp As String = Nothing
            Select Case mode
                Case 1
                    Temp = Configuration.ConfigurationManager.AppSettings(KEYSTR)
                Case 2
                    Temp = Configuration.ConfigurationManager.ConnectionStrings(KEYSTR).ConnectionString
            End Select
            Return Temp
        Catch ex As Exception
            Return Nothing
        End Try
    End Function

    ''' <summary>
    ''' 添加Appsetting节点值
    ''' </summary>
    ''' <param name="KEYSTR">key键</param>
    ''' <param name="VALSTR">value值</param>
    ''' <returns></returns>
    Public Shared Function Insert_Config(ByVal KEYSTR As String, ByVal VALSTR As String, ByVal mode As App_mode) As Boolean
        Try
            Select Case mode
                Case 1
                    If Configuration.ConfigurationManager.AppSettings(KEYSTR) = Nothing Then
                        App_set.Settings.Add(New Configuration.KeyValueConfigurationElement(KEYSTR, VALSTR))
                    Else
                        Return False
                    End If
                Case 2
                    App_connection.ConnectionStrings.Add(New Configuration.ConnectionStringSettings(KEYSTR, VALSTR))
            End Select
            ConFig.Save(Configuration.ConfigurationSaveMode.Modified)
            Configuration.ConfigurationManager.RefreshSection("appSettings")
            Configuration.ConfigurationManager.RefreshSection("connectionStrings")
            Return True
        Catch ex As Exception
            Return False
        End Try
    End Function

    ''' <summary>
    ''' 修改节点值(注意:修改后,App.config文件中节点值没有更改,而是exe.config的配置值更改,不影响正常读取)
    ''' </summary>
    ''' <param name="KEYSTR">key键</param>
    ''' <param name="VALSTR">value值</param>
    ''' <returns></returns>
    Public Shared Function Fix_Config(ByVal KEYSTR As String, ByVal VALSTR As String, ByVal mode As App_mode) As Boolean
        Try
            Select Case mode
                Case 1
                    App_set.Settings(KEYSTR).Value = VALSTR
                Case 2
                    App_connection.ConnectionStrings(KEYSTR).ConnectionString = VALSTR
            End Select
            ConFig.Save(Configuration.ConfigurationSaveMode.Modified)
            Configuration.ConfigurationManager.RefreshSection("appSettings")
            Configuration.ConfigurationManager.RefreshSection("connectionStrings")
            Return True
        Catch ex As Exception
            Return False
        End Try
    End Function

    ''' <summary>
    ''' 删除appconfig节点值
    ''' </summary>
    ''' <param name="KEYSTR">key键</param>
    ''' <returns></returns>
    Public Shared Function Del_Config(ByVal KEYSTR As String, ByVal mode As App_mode) As Boolean
        Try
            Select Case mode
                Case 1
                    App_set.Settings.Remove(KEYSTR)
                Case 2
                    App_connection.ConnectionStrings.Remove(KEYSTR)
            End Select
            ConFig.Save(Configuration.ConfigurationSaveMode.Modified)
            Configuration.ConfigurationManager.RefreshSection("appSettings")
            Configuration.ConfigurationManager.RefreshSection("connectionStrings")
            Return True
        Catch ex As Exception
            Return False
        End Try
    End Function

End Class