DataContractSerializer - how can I output the xml to a string (as opposed to a file)

Question

I had a quick question regarding the datacontractserializer. Maybe it's more of a stream question. I found a piece of code that writes the xml to a filestream. I basically don't want the file and just need the string output.

public static string DataContractSerializeObject<T>(T objectToSerialize)
{   
    var fs = new FileStream("test.xml", FileMode.OpenOrCreate);
    var serializer = new DataContractSerializer(typeof(T));
    serializer.WriteObject(fs, objectToSerialize);
    fs.Close();
    return fs.ToString();
}

fs.ToString() is obviously not what I'm looking for. What stream or writer etc, can I use just to return the proper string and not create a file? I did look at the XML the filestream created and it's exactly what I'm looking for. The XmlSerializer wrote the XML a bit strange and I prefer the output of the DataContractSerializer in this case. Can anyone point me in the right direction?

marc_s · Accepted Answer · 2013-02-28T10:13:21.493

73

Something like this - put your output into a MemoryStream and then read that back in:

public static string DataContractSerializeObject<T>(T objectToSerialize)
{
    using(MemoryStream memStm = new MemoryStream())
    {
        var serializer = new DataContractSerializer(typeof(T));
        serializer.WriteObject(memStm, objectToSerialize);

        memStm.Seek(0, SeekOrigin.Begin);

        using(var streamReader = new StreamReader(memStm))
        {
             string result = streamReader.ReadToEnd();
             return result;
        }
    }
}

edited Feb 28 '13 at 10:13

answered Jul 13 '10 at 15:37

marc_s

732,580
175
1,330
1,459

3

Looks like you interchanged the parameter, it should be memStm.Seek(0,SeekOrigin.Begin); – xar Jul 26 '12 at 08:29
@xar: yes, you're absolutely right - thanks for spotting that mistake - I fixed it now – marc_s Jul 26 '12 at 08:32

Pat · Answer 2 · 2016-06-28T16:40:38.140

29

Thanks to @xr280xr for pointing out my forgotten StringWriter disposal in the first draft.

/// <summary>
/// Converts this instance to XML.
/// </summary>
/// <returns>XML representing this instance.</returns>
public string ToXml()
{
    var serializer = new DataContractSerializer(this.GetType());
    using (var output = new StringWriter())
    using (var writer = new XmlTextWriter(output) { Formatting = Formatting.Indented })
    {
        serializer.WriteObject(writer, this);
        return output.GetStringBuilder().ToString();
    }
}

edited Jun 28 '16 at 16:40

answered Aug 06 '10 at 14:35

Pat

16,515
15
95
114

1

Your StringWriter should be disposed as well. – xr280xr Dec 11 '13 at 20:56
7

The stacked usings do just that. – StingyJack Feb 05 '15 at 21:33
1

This would also make a great extension method for DataContractSerializer (and analogously for XmlSerializer). `public static string WriteObjectToString(this DataContractSerializer serializer, object obj){...}` – JamesFaix May 18 '16 at 15:32

score 20 · Answer 3 · answered Mar 14 '13 at 14:14

20

And even easier:

var serializer = new DataContractSerializer(typeof(T));
var sb = new StringBuilder();
using (var writer = XmlWriter.Create(sb))
{
    serializer.WriteObject(writer, objectToSerialize);
    writer.Flush();
    return sb.ToString();
}

answered Mar 14 '13 at 14:14

root

2,327
1
22
18

score 3 · Answer 4 · edited May 23 '17 at 11:33

3

I suggest combining the methods given by Pat and marc_s:

public static string DataContractSerializeObject<T>(T objectToSerialize)
{
    using (var output = new StringWriter())
    using (var writer = new XmlTextWriter(output) {Formatting = Formatting.Indented})
    {
        new DataContractSerializer(typeof (T)).WriteObject(writer, objectToSerialize);
        return output.GetStringBuilder().ToString();
    }
}

edited May 23 '17 at 11:33

Community

1
1

answered May 28 '13 at 20:31

Ohad Schneider

36,600
15
168
198

This is Pat's method with marc_s's method signature. – HappyNomad Mar 12 '14 at 04:15

score 2 · Answer 5 · answered Nov 12 '15 at 22:45

2

A variant of @root's answer:

var serializer = new DataContractSerializer(typeof(T));
var sb = new StringBuilder();
using (var writer = XmlWriter.Create(sb))
{
    serializer.WriteObject(writer, objectToSerialize);
}

return sb.ToString();

answered Nov 12 '15 at 22:45

Johan Larsson

17,112
9
74
88

DataContractSerializer - how can I output the xml to a string (as opposed to a file)

5 Answers5

Linked