ASP.Net MVC - Read File from HttpPostedFileBase without save

A slight change to Thangamani Palanisamy answer, which allows the Binary reader to be disposed and corrects the input length issue in his comments.

string result = string.Empty;

using (BinaryReader b = new BinaryReader(file.InputStream))
{
  byte[] binData = b.ReadBytes(file.ContentLength);
  result = System.Text.Encoding.UTF8.GetString(binData);
}

This can be done using httpPostedFileBase class returns the HttpInputStreamObject as per specified here

You should convert the stream into byte array and then you can read file content

Please refer following link

http://msdn.microsoft.com/en-us/library/system.web.httprequest.inputstream.aspx]

Hope this helps

UPDATE :

The stream that you get from your HTTP call is read-only sequential (non-seekable) and the FileStream is read/write seekable. You will need first to read the entire stream from the HTTP call into a byte array, then create the FileStream from that array.

Taken from here

// Read bytes from http input stream
BinaryReader b = new BinaryReader(file.InputStream);
byte[] binData = b.ReadBytes(file.ContentLength);

string result = System.Text.Encoding.UTF8.GetString(binData);

An alternative is to use StreamReader.

public void FunctionName(HttpPostedFileBase file)
{
    string result = new StreamReader(file.InputStream).ReadToEnd();
}