A simple CSV file

csv.fs

type Csv private(headers : string[], data : string [] []) = 
     
     let headers = ResizeArray<string>(headers)
     let data = ResizeArray(data |> Array.map (ResizeArray)) 

     static member Empty = Csv([||], [||])

     static member Read(file:string) = 
            let csv = CsvFile.Load(file)
            let headers = 
                match csv.Headers with
                | Some hs -> hs 
                | None -> failwithf "The csv file must have headers"

            new Csv(headers, [| for header in headers do yield [|for row in csv.Rows -> row.GetColumn(header)|] |])

     member x.GetValue(col, indx) = 
        match data |> Seq.tryItem indx with
        | Some row ->
            headers 
            |> Seq.tryFindIndex ((=) col)
            |> Option.bind (fun colIndx -> row |> Seq.tryItem colIndx)
        | None -> None

     member x.SetValue(col, indx, value) = 
        match data |> Seq.tryItem indx with
        | Some row ->
            match headers |> Seq.tryFindIndex ((=) col) with
            | Some colIndex ->
                row.Insert(colIndex, value)
            | None -> 
                headers.Add(col)
                row.Insert(headers.Count - 1, value) 
        | None -> 
            let row = ResizeArray<_>()
            match headers |> Seq.tryFindIndex ((=) col) with
            | Some colIndex ->
                row.Insert(colIndex, value)
            | None -> 
                headers.Add(col)
                row.Insert(headers.Count - 1, value)
            data.Insert(indx, row) 

     member x.Data 
        with get() = 
            [|
                yield headers |> Seq.toArray
                for row in data do
                    yield [| for value in row -> value |]
            |]
    
     override x.ToString() = 
        let sb = new Text.StringBuilder()
        for row in x.Data do 
            sb.AppendLine(String.concat "," row) |> ignore
        sb.ToString()

     member x.Save(path) = 
        IO.File.WriteAllText(path, x.ToString())