Use NetCDF4-C in Unity - c++

Question

this is my first time posting (after lurking for years).
A project I will be tackling is to use NetCDF4 (.nc) files in Unity on Windows. I will be using Unity 5.4.0f3 and Windows 10, and I have developed in Unity before and am familiar with C# and JavaScript, but NetCDF only has C, Java, and Fortran APIs, although there are wrappers in Python, C++, and others (source: https://www.unidata.ucar.edu/publications/factsheets/current/factsheet_netcdf.pdf).
So my specific question is how do I call NetCDF4-C functions (nc_get_vara_float(), nc_open, etc) in C# for use in Unity?
What I've tried so far:
To start, I googled specifically for NetCDF4-C + Unity tutorials/attempts, but did not find anything, so instead I have been looking into the compatibility of calling C functions from C#. I am currently working on a project on Linux with NetCDF4-C and written custom wrapper functions for the netcdf.h functions, so I was hoping I could reuse my code there.
I attempted to follow this SO post (Is it possible to call a C function from C#.Net) but get an error in Unity when trying to Play: "DllNotFoundException: test.so" (my file was named "test.c"). From the comments, it seems Linux uses .so files but Windows uses .dll, and I was not sure how to generate a .dll of a C file.
I looked up another post on that (How to write a DLL file in C?) and downloaded Visual Studio to follow along. While VS was downloading, I looked up how to use GCC to compile (Creating a DLL in GCC or Cygwin?), and used the Bash subsystem ("Bash on Ubuntu on Windows" terminal) but got a handful of errors that indicated the code from the previous link (2nd SO link in this post) were for C++, so I stopped working with GCC.
Once VS finished installing, I went back to trying to use VS to create the .dll, and attempted to combine the solutions from both SO posts (1 and 2) so that I would be able to use the .dll file containing C code in Unity, but to no avail: I get the same error but just with a different extension (and different name on purpose): "DllNotFoundException: Win32Project1.dll".
The code I have is as follows:
test.cs (used in Unity and attaches to a Component):
using UnityEngine;
using System.Collections;
using System.Runtime.InteropServices;
public class test : MonoBehaviour {
[DllImport("Win32Project1.dll", EntryPoint="DisplayHelloFromMyDLL")]
public static extern void DisplayHelloFromMyDLL ();
// Use this for initialization
void Start () {
DisplayHelloFromMyDLL();
}
// Update is called once per frame
void Update () {
}
}
Win32Project1.dll (created and built in Visual Studio):
#include <stdio.h>
extern "C"
{
__declspec(dllexport) void DisplayHelloFromMyDLL()
{
printf("Hello DLL.\n");
}
}