c# - IE7 上的 .aspx 页面 Response.BinaryWrite 图像

Question

我维护一个具有 .aspx 页面的应用程序，该页面从数据库加载图像并使用 Response.BinaryWrite() 将其写回客户端。不久前这还很有效。有两件事发生了变化，我们将应用程序升级到了 .NET 3.5，他们将工作中的所有计算机升级到了 IE7。

在 Firefox 上一切正常，但在 IE7 中我得到的只是一个红色的 X。所以我认为这个问题与 IE7 有关？是否有安全设置可以阻止它从 .aspx 表单加载图像？它已设置为根据内容类型而不是扩展名显示。

这是一些代码。就像我说的，我只是维护这个应用程序，而不是编写它。我知道使用 Session 并不是一个很好的方法，但这就是我所拥有的，并且 switch 语句只是一个“wtf？”。

<asp:image id="imgContent" runat="server" Visible="true" ImageUrl="ProductContentFormImage.aspx"></asp:image>

    protected void Page_Load(object sender, System.EventArgs e)
    {
        Hashtable hshContentBinary = (Hashtable)Session["hshContentBinary"];
        byte[] content = (byte[]) hshContentBinary["content"];
        string extension = (string) hshContentBinary["extension"];


        string contentTypePrefix = "application";
        switch(extension.ToLower())
        {
            case "gif":
            case "jpg":
            case "bmp":
                contentTypePrefix = "image";
                break;
            case "tif":
                contentTypePrefix = "image";
                break;
            case "tiff":
                contentTypePrefix = "image";
                break;
            case "eps":
                contentTypePrefix = "image";
                break;
            default:
                Response.AppendHeader( 
                    "Content-disposition",
                    "attachment; filename=content." + extension );
                break;
        }
        Response.ContentType = contentTypePrefix + "/" + extension;
        Response.BinaryWrite(content);
    }

编辑:

好的，我听从了你的建议，并通过更多的研究，我将方法更改为以下，但它仍然不起作用。

protected void Page_Load(object sender, System.EventArgs e)
{
    Hashtable hshContentBinary = (Hashtable)Session["hshContentBinary"];
    byte[] content = (byte[]) hshContentBinary["content"];
    string extension = (string) hshContentBinary["extension"];
    string contentType;
    string contentDisposition = "inline; filename=content." + extension;

    Response.ClearContent();
    Response.ClearHeaders();
    Response.Clear();

    switch(extension.ToLower())
    {
        case "gif":
            contentType = "image/gif";
            break;
        case "jpg":
        case "jpe":
        case "jpeg":
            contentType = "image/jpeg";
            break;
        case "bmp":
            contentType = "image/bmp";
            break;
        case "tif":
        case "tiff":
            contentType = "image/tiff";
            break;
        case "eps":
            contentType = "application/postscript";
            break;
        default:
            contentDisposition = "attachment; filename=content." + extension;
            contentType = "application/" + extension.ToLower();
            break;
    }

    Response.Buffer = true;
    Response.Expires = 0;
    Response.ContentType = contentType;
    Response.AddHeader("Content-Length", content.Length.ToString());
    Response.AddHeader("Content-disposition", contentDisposition);
    Response.Cache.SetCacheability(HttpCacheability.NoCache);
    Response.BinaryWrite(content);
    Response.End();
}

Answer 1

您的 mime 类型不正确。这效果更好，至少对于图像来说是这样:

string contentType = "application/" + extension.ToLower();
switch(extension.ToLower()) {
   case "gif": contentType = "image/gif"; break;
   case "jpg":
   case "jpeg":
   case "jpe": contentType = "image/jpeg"; break;
   case "bmp": contentType = "image/bmp"; break;
   case "tif":
   case "tiff": contentType = "image/tiff"; break;
   case "eps": contentType = "application/postscript"; break;
   default:
      Response.AppendHeader( 
         "Content-disposition",
         "attachment; filename=content." + extension );
      break;
}
Response.ContentType = contentType;

Hera 是 mime 类型和文件扩展名，如果您需要添加更多: http://www.w3schools.com/media/media_mimeref.asp