convert excel vba Function to c#

Question

I have the vba excel function convert my string text to hash.

Private Function HashString(inputText As String, Optional secretKey = "") As String
    Dim asc As Object
    Dim enc As Object
    Dim textToHash() As Byte
    Dim SharedSecretKey() As Byte
    Dim bytes() As Byte
    
    If secretKey = "" Then secretKey = inputText
    
    Set asc = CreateObject("System.Text.UTF8Encoding")
    Set enc = CreateObject("System.Security.Cryptography.HMACSHA1")

    textToHash = asc.GetBytes_4(inputText)
    SharedSecretKey = asc.GetBytes_4(secretKey)
    enc.Key = SharedSecretKey

    bytes = enc.ComputeHash_2((textToHash))
    HashString = EncodeBase64(bytes)
End Function
Private Function EncodeBase64(arrData() As Byte) As String
    Dim objXML As Object
    Dim objNode As Object
    Set objXML = CreateObject("MSXML2.DOMDocument")
    Set objNode = objXML.createElement("b64")
    objNode.DataType = "bin.base64"
    objNode.nodeTypedValue = arrData
    EncodeBase64 = objNode.Text
End Function

I want to use this function on other C# platforms to have the same algorithm output, How to convert this method to C#? Thanks for the help.

Answer 1

thanks Tim Williams. Answer link