asp.net mvc压缩流和删除空格 [英] asp.net mvc compress stream and remove whitespace

问题描述

所以我通过一个动作过滤器压缩我的输出流：

So I am compressing my output stream via an action filter:

var response = filterContext.HttpContext.Response;
response.Filter = new DeflateStream(response.Filter), CompressionMode.Compress);

现在，我也想删除多余的空格。我发现Mads Kristensen的http模块 http：// madskristensen.net/post/a-whitespace-removal-HTTP-module-for-ASPNET-20.aspx 。

Which works great. Now, I would also like to remove the excess whitespace present. I found Mads Kristensen's http module http://madskristensen.net/post/A-whitespace-removal-HTTP-module-for-ASPNET-20.aspx.

public class WhitespaceFilter : Stream {

    // using Mads Kristensen httpModule
    // http://madskristensen.net/post/A-whitespace-removal-HTTP-module-for-ASPNET-20.aspx

    private Stream os;
    private static Regex reg = new Regex(@"^\s+", RegexOptions.Multiline | RegexOptions.Compiled); 

    public WhitespaceFilter(Stream os) {
        this.os = os;
    }

    //methods that need to be overridden from stream
    public override bool CanRead {
        get { return true; }
    }

    public override bool CanSeek {
        get { return true; }
    }

    public override bool CanWrite {
        get { return true; }
    }

    public override void Flush() {
        os.Flush();
    }

    public override long Length {
        get { return 0; }
    }

    private long _position;
    public override long Position {
        get { return _position; }
        set { _position = value; }
    }

    public override int Read(byte[] buffer, int offset, int count) {
        return os.Read(buffer, offset, count);
    }

    public override long Seek(long offset, SeekOrigin origin) {
        return os.Seek(offset, origin);
    }

    public override void SetLength(long value) {
        os.SetLength(value);
    }

    public override void Close() {
        os.Close();
    }

    public override void Write(byte[] buffer, int offset, int count) {
        string html = System.Text.Encoding.Default.GetString(buffer);

        //remove whitespace
        html = reg.Replace(html, string.Empty);

        byte[] outdata = System.Text.Encoding.Default.GetBytes(html);

        //write bytes to stream
        os.Write(outdata, 0, outdata.GetLength(0));
    } 

我添加了WhitespaceFilter类并添加了一个像压缩一样的新过滤器：

I added the WhitespaceFilter class and added a new filter like the compression:

var response = filterContext.HttpContext.Response;
response.Filter = new WhitepaperFilter(response.Filter);

这也很好。

我试过：

var response = filterContext.HttpContext.Response;
response.Filter = new DeflateStream(new WhitespaceFilter(response.Filter), CompressionMode.Compress);

但这会导致一些主要问题。 html得到完全混乱，有时我得到一个330错误。

However this results in some major issues. The html gets completely messed up and sometimes I get an 330 error.

似乎Whitespace过滤器写方法被调用多次。第一次html字符串是好的，但在后续调用它的只是随机字符。

It seems that the Whitespace filter write method gets called multiple times. The first time the html string is fine, but on subsequent calls its just random characters.

我认为这可能是因为流已经放气，但不是空格过滤器使用未触摸的流，然后将结果流传递给DeflateStream调用？

I thought it might be because the stream had been deflated, but isnt the whitespace filter using the untouched stream and then passing the resulting stream to the DeflateStream call?

任何想法？

推荐答案

对于那些得到这么远...你可以做...只是交换流链的顺序：

For those who get this far... you can do it... just swap the order of the stream chaining:

   public override void OnActionExecuting(ActionExecutingContext filterContext)
   {
        var response = filterContext.HttpContext.Response;

        // - COMPRESS
        HttpRequestBase request = filterContext.HttpContext.Request;
        string acceptEncoding = request.Headers["Accept-Encoding"];
        if (!String.IsNullOrEmpty(acceptEncoding))
        {
            acceptEncoding = acceptEncoding.ToUpperInvariant();

            if (acceptEncoding.Contains("GZIP"))
            {
                response.AppendHeader("Content-encoding", "gzip");
                response.Filter = new GZipStream(response.Filter, CompressionMode.Compress);
            }
            else if (acceptEncoding.Contains("DEFLATE"))
            {
                response.AppendHeader("Content-encoding", "deflate");
                response.Filter = new DeflateStream(response.Filter, CompressionMode.Compress);
            }
        }

        // - REMOVE WHITE SPACE
        response.Filter = new WhitespaceFilter(response.Filter);
    }

这篇关于asp.net mvc压缩流和删除空格的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！