I am using a routine that serializes <T>
. It works, but when downloaded to the browser I see a blank page. I can view the page source or open the download in a text editor and I see the xml, but it is in UTF-16 which I think is why browser pages show blank?
How do I modify my serializer routine to return UTF-8 instead of UTF-16?
The XML source returned:
<?xml version="1.0" encoding="utf-16"?>
<ArrayOfString xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<string>January</string>
<string>February</string>
<string>March</string>
<string>April</string>
<string>May</string>
<string>June</string>
<string>July</string>
<string>August</string>
<string>September</string>
<string>October</string>
<string>November</string>
<string>December</string>
<string />
</ArrayOfString>
An example call to the serializer:
DateTimeFormatInfo dateTimeFormatInfo = new DateTimeFormatInfo();
var months = dateTimeFormatInfo.MonthNames.ToList();
string SelectionId = "1234567890";
return new XmlResult<List<string>>(SelectionId)
{
Data = months
};
The Serializer:
public class XmlResult<T> : ActionResult
{
private string filename = DateTime.Now.ToString("ddmmyyyyhhss");
public T Data { private get; set; }
public XmlResult(string selectionId = "")
{
if (selectionId != "")
{
filename = selectionId;
}
}
public override void ExecuteResult(ControllerContext context)
{
HttpContextBase httpContextBase = context.HttpContext;
httpContextBase.Response.Buffer = true;
httpContextBase.Response.Clear();
httpContextBase.Response.AddHeader("content-disposition", "attachment; filename=" + filename + ".xml");
httpContextBase.Response.ContentType = "text/xml";
using (StringWriter writer = new StringWriter())
{
XmlSerializer xml = new XmlSerializer(typeof(T));
xml.Serialize(writer, Data);
httpContextBase.Response.Write(writer);
}
}
}
I am not quite familiar with this part of the framework. But according to the MSDN you can set the content encoding of an HttpResponse like this:
httpContextBase.Response.ContentEncoding = Encoding.UTF8;
After reading your question again I see that this is the tough part. The problem lies within the use of the StringWriter
. Because .NET Strings are always stored as UTF-16 (citation needed ^^) the StringWriter
returns this as its encoding. Thus the XmlSerializer
writes the XML-Declaration as
<?xml version="1.0" encoding="utf-16"?>
To work around that you can write into an MemoryStream like this:
using (MemoryStream stream = new MemoryStream())
using (StreamWriter writer = new StreamWriter(stream, Encoding.UTF8))
{
XmlSerializer xml = new XmlSerializer(typeof(T));
xml.Serialize(writer, Data);
// I am not 100% sure if this can be optimized
httpContextBase.Response.BinaryWrite(stream.ToArray());
}
Other approaches
Another edit: I just noticed this SO answer linked by jtm001. Condensed the solution there is to provide the XmlSerializer
with a custom XmlWriter
that is configured to use UTF8 as encoding.
Athari proposes to derive from the StringWriter
and advertise the encoding as UTF8.
To my understanding both solutions should work as well. I think the take-away here is that you will need one kind of boilerplate code or another...