Ignore specified members field when serialise to Json string

I have a generated WCF client with class similar to the sample below

    public partial class SampleClass
    {
        private bool costFieldSpecified;
        
        private decimal costField;
        
        [System.Xml.Serialization.XmlIgnoreAttribute()]
        public bool CostFieldSpecified
        {
            get
            {
                return this.costFieldSpecified;
            }
            set
            {
                this.costFieldSpecified = value;
            }
        }
        
        [System.Xml.Serialization.XmlElementAttribute(Order=0)]
        public string Cost
        {
            get
            {
                return this.costField;
            }
            set
            {
                this.costField = value;
            }
        }
    }

In my unit test, I instantiate an instance of SampleClass with a value of Cost field but without setting the CostFieldSpecified to true. When I serialise it to Json string, the Cost field’s value is 0 instead of the value I set it. I then realise that if I set the CostFieldSpecified to true, the serialised Json string will have the correct Cost value that I set. For testing, this could be tedious having to set the Specified fields to true if your class has lots of those.

To solve this, I add a Json Contract Resolver to ignore the Specified field when serialising.

public static class JsonContractResolvers
{
    public static readonly DefaultContractResolver IgnoreIsSpecifiedMembersResolver =
        new DefaultContractResolver { IgnoreIsSpecifiedMembers = true };
}

This is how to use it

var jsonSerialiserSettings = new JsonSerializerSettings { ContractResolver = JsonContractResolvers.IgnoreIsSpecifiedMembersResolver };
var json = JsonConvert.SerializeObject(testObject, Formatting.Indented, jsonSerialiserSettings);