Find text in textbox in word document

I got a vb.net code and works correctly. Can anyone help to convert it to c#?

 

 

Dim word As New Word.Application
        Dim doc As Word.Document
        word.Documents.Open("c:\abc.doc")
        word.Visible = True
        doc = word.ActiveDocument
        FindandReplace(doc, "vbcode", "csharp code")
    Sub FindandReplace(ByVal doc As Word.Document, ByVal Findtext As String, ByVal Replacetext As String)
        Dim myStoryRange = doc.Range()
        'First search the main document using the Selection
        With myStoryRange.Find
            .Text = Findtext
            .Replacement.Text = Replacetext
            .Forward = True
            .Wrap = Word.WdFindWrap.wdFindContinue
            .Format = False
            .MatchCase = False
            .MatchWholeWord = False
            .MatchWildcards = False
            .MatchSoundsLike = False
            .MatchAllWordForms = False
            .Execute(Replace:=Word.WdReplace.wdReplaceAll)
        End With
        'Now search all other stories using Ranges
        For Each myStoryRange In doc.StoryRanges
            If myStoryRange.StoryType <> Word.WdStoryType.wdMainTextStory Then
                With myStoryRange.Find
                    .Text = Findtext
                    .Replacement.Text = Replacetext
                    .Wrap = Word.WdFindWrap.wdFindContinue
                    .Execute(Replace:=Word.WdReplace.wdReplaceAll)
                End With
                Do While Not (myStoryRange.NextStoryRange Is Nothing)
                    myStoryRange = myStoryRange.NextStoryRange
                    With myStoryRange.Find
                        .Text = Findtext
                        .Replacement.Text = Replacetext
                        .Wrap = Word.WdFindWrap.wdFindContinue
                        .Execute(Replace:=Word.WdReplace.wdReplaceAll)
                    End With
                Loop
            End If
        Next myStoryRange
    End Sub