Recommended way to create an ActionResult with a file extension

Question

I need to create an ActionResult in an ASP.NET MVC application which has a .csv filetype.

I will provide a \'do not call\' email list to my marketing partners and i

Answer 1

I think your Response MUST contain "Content-Disposition" header in this case. Create custom ActionResult like this:

public class MyCsvResult : ActionResult {

    public string Content {
        get;
        set;
    }

    public Encoding ContentEncoding {
        get;
        set;
    }

    public string Name {
        get;
        set;
    }

    public override void ExecuteResult(ControllerContext context) {
        if (context == null) {
            throw new ArgumentNullException("context");
        }

        HttpResponseBase response = context.HttpContext.Response;

        response.ContentType = "text/csv";

        if (ContentEncoding != null) {
            response.ContentEncoding = ContentEncoding;
        }

        var fileName = "file.csv";

        if(!String.IsNullOrEmpty(Name)) {
            fileName = Name.Contains('.') ? Name : Name + ".csv";
        }

        response.AddHeader("Content-Disposition",
            String.Format("attachment; filename={0}", fileName));

        if (Content != null) {
            response.Write(Content);
        }
    }
}

And use it in your Action instead of ContentResult:

return new MyCsvResult {
    Content = Emails.Aggregate((a,b) => a + Environment.NewLine + b)
    /* Optional
     * , ContentEncoding = ""
     * , Name = "DoNotEmailList.csv"
     */
};