Which FIle Form Field For C# Request.Files[n].FileName

Question

If I have a HTML form with multiple input file fields (where 'N' is a unique number);

<input type="file" name="inputFileN"> 

Then in the C# code;

string inFile = System.IO.Path.GetFileName(Request.Files[M].FileName)

Is there any way I can ascertain the value of 'M' from the Request data so I can match against a specific HTML input file-type field ?

This is in a situation where the end-user can update the fields on an edit form and it works ok for for all field types apart from the file-type field.

Answer 1

All of the necessary data is in HttpContext.Request.Files; specifically, in HttpContext.Request.Files.AllKeys:

//HttpContext is a member of `System.Web.Mvc.Controller`,
//accessible in controllers that inherit from `System.Web.Mvc.Controller`.
System.Web.HttpFileCollectionBase files = HttpContext.Request.Files;
string[] fieldNames = files.AllKeys;
for (int i = 0; i < fieldNames.Length; ++i)
{
    string field = fieldNames[i]; //The 'name' attribute of the html form
    System.Web.HttpPostedFileBase file = files[i];
    string fileName = files[i].FileName; //The path to the file on the client computer
    int len = files[i].ContentLength; //The length of the file
    string type = files[i].ContentType; //The file's MIME type
    System.IO.Stream stream = files[i].InputStream; //The actual file data
}