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Imports System.Configuration
Public Class AppSettings

    Private config As Configuration

    Public Sub AppSetting()
        config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)
    End Sub

    Public Function GetConnectionString(ByVal key As String) As String
        Return config.ConnectionStrings.ConnectionStrings(key).ConnectionString
    End Function

    Public Sub SaveConnectionString(ByVal key As String, ByVal value As String)
        config.ConnectionStrings(key).ConnectionString = value
        config.ConnectionStrings(key).ProviderName = "MySql.Data.MySqlClient"
        config.Save(configurationSaveMode.Modified)
    End Sub

End Class