What is the best way to return XML from a controller’s action in ASP.NET MVC? There is a nice way to return JSON, but not for XML. Do I really need to route the XML through a View, or should I do the not-best-practice way of Response.Write-ing it?
Answers:
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Method 1
return this.Content(xmlString, "text/xml");
Method 2
Use MVCContrib‘s XmlResult Action.
For reference here is their code:
public class XmlResult : ActionResult
{
private object objectToSerialize;
/// <summary>
/// Initializes a new instance of the <see cref="XmlResult"/> class.
/// </summary>
/// <param name="objectToSerialize">The object to serialize to XML.</param>
public XmlResult(object objectToSerialize)
{
this.objectToSerialize = objectToSerialize;
}
/// <summary>
/// Gets the object to be serialized to XML.
/// </summary>
public object ObjectToSerialize
{
get { return this.objectToSerialize; }
}
/// <summary>
/// Serialises the object that was passed into the constructor to XML and writes the corresponding XML to the result stream.
/// </summary>
/// <param name="context">The controller context for the current request.</param>
public override void ExecuteResult(ControllerContext context)
{
if (this.objectToSerialize != null)
{
context.HttpContext.Response.Clear();
var xs = new System.Xml.Serialization.XmlSerializer(this.objectToSerialize.GetType());
context.HttpContext.Response.ContentType = "text/xml";
xs.Serialize(context.HttpContext.Response.Output, this.objectToSerialize);
}
}
}
Method 3
If you’re building the XML using the excellent Linq-to-XML framework, then this approach will be helpful.
I create an XDocument in the action method.
public ActionResult MyXmlAction()
{
// Create your own XDocument according to your requirements
var xml = new XDocument(
new XElement("root",
new XAttribute("version", "2.0"),
new XElement("child", "Hello World!")));
return new XmlActionResult(xml);
}
This reusable, custom ActionResult serialises the XML for you.
public sealed class XmlActionResult : ActionResult
{
private readonly XDocument _document;
public Formatting Formatting { get; set; }
public string MimeType { get; set; }
public XmlActionResult(XDocument document)
{
if (document == null)
throw new ArgumentNullException("document");
_document = document;
// Default values
MimeType = "text/xml";
Formatting = Formatting.None;
}
public override void ExecuteResult(ControllerContext context)
{
context.HttpContext.Response.Clear();
context.HttpContext.Response.ContentType = MimeType;
using (var writer = new XmlTextWriter(context.HttpContext.Response.OutputStream, Encoding.UTF8) { Formatting = Formatting })
_document.WriteTo(writer);
}
}
You can specify a MIME type (such as application/rss+xml) and whether the output should be indented if you need to. Both properties have sensible defaults.
If you need an encoding other than UTF8, then it’s simple to add a property for that too.
Method 4
If you are only interested to return xml through a request, and you have your xml “chunk”, you can just do (as an action in your controller):
public string Xml()
{
Response.ContentType = "text/xml";
return yourXmlChunk;
}
Method 5
There is a XmlResult (and much more) in MVC Contrib. Take a look at http://www.codeplex.com/MVCContrib
Method 6
I’ve had to do this recently for a Sitecore project which uses a method to create an XmlDocument from a Sitecore Item and its children and returns it from the controller ActionResult as a File. My solution:
public virtual ActionResult ReturnXml()
{
return File(Encoding.UTF8.GetBytes(GenerateXmlFeed().OuterXml), "text/xml");
}
Method 7
Finally manage to get this work and thought I would document how here in the hopes of saving others the pain.
Environment
- VS2012
- SQL Server 2008R2
- .NET 4.5
- ASP.NET MVC4 (Razor)
- Windows 7
Supported Web Browsers
- FireFox 23
- IE 10
- Chrome 29
- Opera 16
- Safari 5.1.7 (last one for Windows?)
My task was on a ui button click, call a method on my Controller (with some params) and then have it return an MS-Excel XML via an xslt transform. The returned MS-Excel XML would then cause the browser to popup the Open/Save dialog. This had to work in all the browsers (listed above).
At first I tried with Ajax and to create a dynamic Anchor with the “download” attribute for the filename,
but that only worked for about 3 of the 5 browsers(FF, Chrome, Opera) and not for IE or Safari.
And there were issues with trying to programmatically fire the Click event of the anchor to cause the actual “download”.
What I ended up doing was using an “invisible” IFRAME and it worked for all 5 browsers!
So here is what I came up with:
[please note that I am by no means an html/javascript guru and have only included the relevant code]
HTML (snippet of relevant bits)
<div id="docxOutput">
<iframe id="ifOffice" name="ifOffice" width="0" height="0"
hidden="hidden" seamless='seamless' frameBorder="0" scrolling="no"></iframe></div>
JAVASCRIPT
//url to call in the controller to get MS-Excel xml
var _lnkToControllerExcel = '@Url.Action("ExportToExcel", "Home")';
$("#btExportToExcel").on("click", function (event) {
event.preventDefault();
$("#ProgressDialog").show();//like an ajax loader gif
//grab the basket as xml
var keys = GetMyKeys();//returns delimited list of keys (for selected items from UI)
//potential problem - the querystring might be too long??
//2K in IE8
//4096 characters in ASP.Net
//parameter key names must match signature of Controller method
var qsParams = [
'keys=' + keys,
'locale=' + '@locale'
].join('&');
//The element with id="ifOffice"
var officeFrame = $("#ifOffice")[0];
//construct the url for the iframe
var srcUrl = _lnkToControllerExcel + '?' + qsParams;
try {
if (officeFrame != null) {
//Controller method can take up to 4 seconds to return
officeFrame.setAttribute("src", srcUrl);
}
else {
alert('ExportToExcel - failed to get reference to the office iframe!');
}
} catch (ex) {
var errMsg = "ExportToExcel Button Click Handler Error: ";
HandleException(ex, errMsg);
}
finally {
//Need a small 3 second ( delay for the generated MS-Excel XML to come down from server)
setTimeout(function () {
//after the timeout then hide the loader graphic
$("#ProgressDialog").hide();
}, 3000);
//clean up
officeFrame = null;
srcUrl = null;
qsParams = null;
keys = null;
}
});
C# SERVER-SIDE (code snippet)
@Drew created a custom ActionResult called XmlActionResult which I modified for my purpose.
Return XML from a controller’s action in as an ActionResult?
My Controller method (returns ActionResult)
- passes the keys parameter to a SQL Server stored proc that generates an XML
- that XML is then transformed via xslt into an MS-Excel xml (XmlDocument)
-
creates instance of the modified XmlActionResult and returns it
XmlActionResult result = new XmlActionResult(excelXML, “application/vnd.ms-excel”);
string version = DateTime.Now.ToString(“dd_MMM_yyyy_hhmmsstt”);
string fileMask = “LabelExport_{0}.xml”;
result.DownloadFilename = string.Format(fileMask, version);
return result;
The main modification to the XmlActionResult class that @Drew created.
public override void ExecuteResult(ControllerContext context)
{
string lastModDate = DateTime.Now.ToString("R");
//Content-Disposition: attachment; filename="<file name.xml>"
// must set the Content-Disposition so that the web browser will pop the open/save dialog
string disposition = "attachment; " +
"filename="" + this.DownloadFilename + ""; ";
context.HttpContext.Response.Clear();
context.HttpContext.Response.ClearContent();
context.HttpContext.Response.ClearHeaders();
context.HttpContext.Response.Cookies.Clear();
context.HttpContext.Response.Cache.SetCacheability(System.Web.HttpCacheability.NoCache);// Stop Caching in IE
context.HttpContext.Response.Cache.SetNoStore();// Stop Caching in Firefox
context.HttpContext.Response.Cache.SetMaxAge(TimeSpan.Zero);
context.HttpContext.Response.CacheControl = "private";
context.HttpContext.Response.Cache.SetLastModified(DateTime.Now.ToUniversalTime());
context.HttpContext.Response.ContentType = this.MimeType;
context.HttpContext.Response.Charset = System.Text.UTF8Encoding.UTF8.WebName;
//context.HttpContext.Response.Headers.Add("name", "value");
context.HttpContext.Response.Headers.Add("Last-Modified", lastModDate);
context.HttpContext.Response.Headers.Add("Pragma", "no-cache"); // HTTP 1.0.
context.HttpContext.Response.Headers.Add("Expires", "0"); // Proxies.
context.HttpContext.Response.AppendHeader("Content-Disposition", disposition);
using (var writer = new XmlTextWriter(context.HttpContext.Response.OutputStream, this.Encoding)
{ Formatting = this.Formatting })
this.Document.WriteTo(writer);
}
That was basically it.
Hope it helps others.
Method 8
A simple option that will let you use streams and all that is return File(stream, "text/xml");.
Method 9
use one of these methods
public ContentResult GetXml()
{
string xmlString = "your xml data";
return Content(xmlString, "text/xml");
}
or
public string GetXml()
{
string xmlString = "your xml data";
Response.ContentType = "text/xml";
return xmlString;
}
Method 10
Here is a simple way of doing it:
var xml = new XDocument(
new XElement("root",
new XAttribute("version", "2.0"),
new XElement("child", "Hello World!")));
MemoryStream ms = new MemoryStream();
xml.Save(ms);
return File(new MemoryStream(ms.ToArray()), "text/xml", "HelloWorld.xml");
Method 11
A small variation of the answer from Drew Noakes that use the method Save() of XDocument.
public sealed class XmlActionResult : ActionResult
{
private readonly XDocument _document;
public string MimeType { get; set; }
public XmlActionResult(XDocument document)
{
if (document == null)
throw new ArgumentNullException("document");
_document = document;
// Default values
MimeType = "text/xml";
}
public override void ExecuteResult(ControllerContext context)
{
context.HttpContext.Response.Clear();
context.HttpContext.Response.ContentType = MimeType;
_document.Save(context.HttpContext.Response.OutputStream)
}
}
All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0