MVC Basic Site: Step 3 – Dynamic Layouts and Site Admin with: AJAX, jqGrid, Controller Extensions, HTML Helpers, and more

using System;
using System.Web.Mvc;

namespace MvcBasicSite.Models.Helpers
{
    /// <summary>
    /// Defines the open file in new window action result.
    /// </summary>
    public class OpenFileResult : ActionResult
    {
        /// <summary>
        /// The request IsLocal flag.
        /// </summary>
        private bool _isLocal = false;
        /// <summary>
        /// The virtual path of the file.
        /// </summary>
        public string VirtualPath
        {
            get;
            set;
        }
        /// <summary>
        /// The file name with extension and without path. 
        /// </summary>
        public string FileName
        {
            get;
            set;
        }
        /// <summary>
        /// Gets or sets the content type.
        /// </summary>
        public string  ContentType { get; set; }

        /// <summary>
        /// Initializes a new instance of the OpenFileResult class.
        /// </summary>
        /// <param name="isLocal">The request IsLocal flag.</param>
        /// <param name="virtualPath">The file virtual path or use the default Doc path.</param>
        public OpenFileResult(bool isLocal, string virtualPath)
        {
            _isLocal = isLocal;
            this.VirtualPath = virtualPath;
        }

        /// <summary>
        /// Open the file into a new browser window for known files or let the user to select Open/Save.
        /// </summary>
        /// <param name="context">The current controller context.</param>
        public override void ExecuteResult(ControllerContext context)
        {
            context.HttpContext.Response.Clear();
            context.HttpContext.Response.ClearContent();
            //
            if(this.ContentType != null)
                context.HttpContext.Response.ContentType = ContentType;
            else
                context.HttpContext.Response.AddHeader("content-disposition", "attachment;filename=" + this.FileName);
            //
            context.HttpContext.Response.Cache.SetCacheability(System.Web.HttpCacheability.Public);
            string filePath = (_isLocal ? this.FileName : string.Format("{0}\\{1}", context.HttpContext.Server.MapPath(this.VirtualPath), this.FileName));
            if (System.IO.File.Exists(filePath))
            {
                context.HttpContext.Response.TransmitFile(filePath);
            }
            else
            {
                context.HttpContext.Response.Write(Resources.Resource.OpenFileResultFileNotFound);
            }
            //
            context.HttpContext.Response.End();
        }
    }
}