how to use DataContract to serialize a number to a percentage in the xml output?

Question

I am wondering whether I can customize the xml output like what ToString does. e.g, use % to output 80% rather than 0.8 I also need to deserialize it later...

Thanks.

Answer 1

Don't serialize the property with the number directly. Instead, create a dummy string property that formats and parses the number:

[DataContract]
public class MyClass
{
    // No DataMember attribute here
    public double MyProperty { get; set; }

    // Serialize this property instead
    [DataMember(Name = "MyProperty")]
    private string MyPropertyXml
    {
        get { return MyProperty.ToString("P", CultureInfo.InvariantCulture); }
        set
        {
            if (string.IsNullOrEmpty(value))
            {
                MyProperty = 0;
            }
            else
            {
                string s = value.TrimEnd('%', ' ');
                MyProperty = double.Parse(s, CultureInfo.InvariantCulture) / 100;
            }
        }
    }
}

It produces the following output:

<?xml version="1.0" encoding="utf-16"?>
<MyClass xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/">
  <MyProperty>42.00 %</MyProperty>
</MyClass>