Can I write a file to a folder on a server machine from a Web API app running on it?

Question

I have this code in my Web API app to write to a CSV file:

private void SaveToCSV(InventoryItem invItem, string dbContext)
{
    string csvHeader = "id,pack_size,description,vendor_id,department,subdepartment,unit_cost,unit_list,open_qty,UPC_code,UPC_pack_size,vendor_item,crv_id";

    int dbContextAsInt = 0;
    int.TryParse(dbContext, out dbContextAsInt);
    string csvFilename = string.Format("Platypus{0}.csv", dbContextAsInt);

    string csv = string.Format("{0},{1},{2},{3},{4},{5},{6},{7},{8},{9},{10},{11},{12}", invItem.ID,
        invItem.pksize, invItem.Description, invItem.vendor_id, invItem.dept, invItem.subdept, invItem.UnitCost,
        invItem.UnitList, invItem.OpenQty, invItem.UPC, invItem.upc_pack_size, invItem.vendor_item, invItem.crv_id);

    string existingContents;
    using (StreamReader sr = new StreamReader(csvFilename))
    {
        existingContents = sr.ReadToEnd();
    }

    using (StreamWriter writetext = File.AppendText(csvFilename))
    {
        if (!existingContents.Contains(csvHeader))
        {
            writetext.WriteLine(csvHeader);
        }
        writetext.WriteLine(csv);
    }
}

On the dev machine, the csv file is saved to "C:\Program Files (x86)\IIS Express" by default. In preparation for when it is deployed to its final resting/working place, what do I need to do to get the file to save, e.g., to the server's "Platypi" folder - anything special? Do I have to specifically set certain folder persimmons to allow writing to "Platypi."

Is it simply a matter of changing this line:

string csvFilename = string.Format("Platypus{0}.csv", dbContextAsInt);

...to this:

string csvFilename = string.Format(@"\Platypi\Platypus{0}.csv", dbContextAsInt);

?

Answer 1

Thanks to Patrick Hofman; this is the exact code I am using, and it is saved to the project's App_Data folder:

public static string appDataFolder = HttpContext.Current.Server.MapPath("~/App_Data/");
. . .
string csvFilename = string.Format("Platypus{0}.csv", dbContextAsInt);
string fullSavePath = string.Format("{0}{1}", appDataFolder, csvFilename);