Webmatrix file upload error - file-upload

Question

I am trying to create an upload page where I upload a .swf file and then I add the filename to my database. Previously I have been able to achieve this, however, now it seems to give me the error "Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index" My code is as follows:
#{
Page.Title = "Add Game";
//Variables
var GameName = "";
var Tags = "";
var Gamefile = "";
//Required fields
Validation.RequireField("Name", "Please give the game a name.");
Validation.RequireField("file", "Please upload a file.");
//Maximum name length
Validation.Add("Name",
Validator.StringLength(
maxLength: 100,
errorMessage: "Name must be less than 100 characters")
);
//SWF file validation
Validation.Add("file",
Validator.Regex(#"^.*\.(swf|SWF)$", "Invalid filetype, you must upload a .swf flash file")
);
if (IsPost && Validation.IsValid()) {
var db = Database.Open("Surgestuff");
var gCat = "";
var fileData = Request.Files[0];
var fileName = Guid.NewGuid().ToString() + ".swf";
var fileSavePath = Server.MapPath("~/upload/" + fileName);
var AddBy = WebSecurity.CurrentUserName;
gCat=Request["formCat"];
Gamefile = fileName;
fileData.SaveAs(fileSavePath);
var SQLINSERT = "INSERT INTO Games (Name, file_path, Category, AddBy) " + "VALUES (#0, #1, #2, #3)";
db.Execute(SQLINSERT, GameName, Gamefile, gCat, AddBy);
Response.Redirect("~/Games");
}
}
And for some reason, even when i have a file submitted, the
var fileData = Request.Files[0]; gives me that error

Answer 1

The Web Pages 2 Validation helpers do not work with an input type="file". They only work with elements that are included in the Request.Form collection. A file upload appears in the Request.Files collection.
There are a couple of approaches you can take to validate the file upload. You can use ModelState:
if(IsPost && Request.Files[0].ContentLength == 0){
ModelState.AddError("file", "You must choose a file");
}
if (IsPost && Validation.IsValid() && ModelState.IsValid) {
// etc
Or you can add a hidden field, and when the form is submitted, populate its value with that of the file upload via JavaScript. Then you can use the new Validation helpers as you are currently trying to do, but on the hidden field instead.