Ï "¿characters attached to the beginning of each file

Question

I loaded the HttpHandler class, which combines JS files into a single file and continues to add  characters at the beginning of each file that it combines.

Any ideas on what causes this? Could it be that the processed files are written to the cache and that the cache stores / displays it?

Any input is welcome.

 using System; using System.Net; using System.IO; using System.IO.Compression; using System.Text; using System.Configuration; using System.Web; public class HttpCombiner : IHttpHandler { private const bool DO_GZIP = false; private readonly static TimeSpan CACHE_DURATION = TimeSpan.FromDays(30); public void ProcessRequest (HttpContext context) { HttpRequest request = context.Request; // Read setName, contentType and version. All are required. They are // used as cache key string setName = request["s"] ?? string.Empty; string contentType = request["t"] ?? string.Empty; string version = request["v"] ?? string.Empty; // Decide if browser supports compressed response bool isCompressed = DO_GZIP && this.CanGZip(context.Request); // Response is written as UTF8 encoding. If you are using languages // like Arabic, you should change this to proper encoding UTF8Encoding encoding = new UTF8Encoding(false); // If the set has already been cached, write the response directly // from cache. Otherwise generate the response and cache it if (!this.WriteFromCache(context, setName, version, isCompressed, contentType)) { using (MemoryStream memoryStream = new MemoryStream(5000)) { // Decide regular stream or GZipStream based on whether the // response can be cached or not using (Stream writer = isCompressed ? (Stream)(new GZipStream(memoryStream, CompressionMode.Compress)) : memoryStream) { // Load the files defined in <appSettings> and process // each file string setDefinition = System.Configuration .ConfigurationManager.AppSettings[setName] ?? ""; string[] fileNames = setDefinition.Split( new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries); foreach (string fileName in fileNames) { byte[] fileBytes = this.GetFileBytes( context, fileName.Trim(), encoding); writer.Write(fileBytes, 0, fileBytes.Length); } writer.Close(); } // Cache the combined response so that it can be directly // written in subsequent calls byte[] responseBytes = memoryStream.ToArray(); context.Cache.Insert( GetCacheKey(setName, version, isCompressed), responseBytes, null, System.Web.Caching.Cache.NoAbsoluteExpiration, CACHE_DURATION); // Generate the response this.WriteBytes(responseBytes, context, isCompressed, contentType); } } } private byte[] GetFileBytes(HttpContext context, string virtualPath, Encoding encoding) { if (virtualPath.StartsWith("http://", StringComparison.InvariantCultureIgnoreCase)) { using (WebClient client = new WebClient()) { return client.DownloadData(virtualPath); } } else { string physicalPath = context.Server.MapPath(virtualPath); byte[] bytes = File.ReadAllBytes(physicalPath); // TODO: Convert unicode files to specified encoding. // For now, assuming files are either ASCII or UTF8 return bytes; } } private bool WriteFromCache(HttpContext context, string setName, string version, bool isCompressed, string contentType) { byte[] responseBytes = context.Cache[GetCacheKey(setName, version, isCompressed)] as byte[]; if (null == responseBytes || 0 == responseBytes.Length) return false; this.WriteBytes(responseBytes, context, isCompressed, contentType); return true; } private void WriteBytes(byte[] bytes, HttpContext context, bool isCompressed, string contentType) { HttpResponse response = context.Response; response.AppendHeader("Content-Length", bytes.Length.ToString()); response.ContentType = contentType; if (isCompressed) response.AppendHeader("Content-Encoding", "gzip"); context.Response.Cache.SetCacheability(HttpCacheability.Public); context.Response.Cache.SetExpires(DateTime.Now.Add(CACHE_DURATION)); context.Response.Cache.SetMaxAge(CACHE_DURATION); context.Response.Cache.AppendCacheExtension( "must-revalidate, proxy-revalidate"); response.OutputStream.Write(bytes, 0, bytes.Length); response.Flush(); } private bool CanGZip(HttpRequest request) { string acceptEncoding = request.Headers["Accept-Encoding"]; if (!string.IsNullOrEmpty(acceptEncoding) && (acceptEncoding.Contains("gzip") || acceptEncoding.Contains("deflate"))) return true; return false; } private string GetCacheKey(string setName, string version, bool isCompressed) { return "HttpCombiner." + setName + "." + version + "." + isCompressed; } public bool IsReusable { get { return true; } } } 

Answer 1

OK, I debugged your code.

Tag icons appear in the original stream when files are read from disk:

 byte[] bytes = File.ReadAllBytes(physicalPath); // TODO: Convert unicode files to specified encoding. For now, assuming // files are either ASCII or UTF8 

If you read the files correctly, you can get rid of the marks.

Answer 2

The symbols ï "are UTF specification markers .

Answer 3

Its character is UTF Byte (BOM) .

It will be at the beginning of each file, but your editor will ignore them there. When they are concatenated, they are in the middle, so you see them.

Answer 4

I think this is Byte Order Estimation (BOM) for UTF-8 encoded files. This label allows you to determine in which encoding the file is stored.

Answer 5

If you have the contents of the file in a line, .Trim () will easily remove the “spec.”

You may not be able to do this, or you may want spaces at the end of the file, but this is certainly an option.

For spaces .js doesn't matter, so this might work.

Answer 6

Check how your js files are encoded and provide the same encoding in the code that performs reading and concatenation. These two characters usually indicate unicode.

Answer 7

These characters are UTF-8 specification. It doesn't look like they are coming from a gzipped stream. Most likely, they are inserted into the response stream, so I suggest clearing the answer before working with it:

 context.Response.Clear(); 

Answer 8

You have not published what the actual solution is. Here is my soul. On the line where it reads the file into memory, I found a strange way to delete the specification:

 byte[] bytes = File.ReadAllBytes(physicalPath); String ss = new StreamReader(new MemoryStream(bytes), true).ReadToEnd(); byte[] b = StrToByteArray(ss); return b; 

And you also need this function:

 public static byte[] StrToByteArray(string str) { System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding(); return encoding.GetBytes(str); } 

Nitech