Unable to use fileInfo and fileStream in PCL project for Xamarin Project

I'm currently facing an issue with using fileInfo and fileStream related codes in my Xamarin PCL Project as Visual Studio will give an error saying that the type or namespace name 'FileInfo' could not be found.

I have already included the using System; and using system.IO statements in the code but it is still not working.

using System;
using System.IO;
using IPShare.Models;
using IPShare.ViewModels; 
using Xamarin.Forms;
using System.Net;
using System.Resources;

using System.Text;
using System.Threading.Tasks;
using PCLStorage;
using System.Net.Http;


namespace IPShare.Views
{
    public partial class ItemsPage : ContentPage
    {
       ItemsViewModel viewModel;
 private async void OnButtonClicked(object sender, EventArgs e)
        {


            // Load file meta data with FileInfo
             FileInfo fileInfo = new FileInfo(path);

            // The byte[] to save the data in
            byte[] data = new byte[fileInfo.Length];

            // Load a filestream and put its content into the byte[]
            using (FileStream fs = fileInfo.OpenRead())
            {
                fs.Read(data, 0, data.Length);
            }

            // Delete the temporary file
            fileInfo.Delete();
       }
    }
}

As I'm new to xamarin and C# any help would be greatly appreciated.