VB.NET Read html all context with HtmlAgilityPack

Imports HtmlAgilityPack
Imports System.Web

    Private Function GetHtmlContext(filePath As String) As String

        Dim htmldoc As New HtmlDocument
        htmldoc.Load(filePath, Encoding.UTF8)
        Dim htmlText As String = htmldoc.DocumentNode.InnerText

        'エンティティ参照の変換
        htmlText = System.Web.HttpUtility.HtmlDecode(htmlText )

        Return htmlText
    End Function