Compare JSON Arrays

How do you compare two similar JSON array set ? I bet that is a scenario you might have across atleast once in your developer life. Let us say you have following two sets of JSONs.

Json Set 1

[
 {
   "SourceLocation":"England",
   "DestinationLocation":"Spain",
   "DeliveryDate":"9/12"
  },
  {
   "SourceLocation":"England",
   "DestinationLocation":"Germany",
   "DeliveryDate":"9/12"
   }
]

Json Set 2

[
  {
    "SourceLocation":"England",
    "DestinationLocation":"Spain",
    "DeliveryDate":"9/12"
   },
   {
     "SourceLocation":"England",
     "DestinationLocation":"Germany",
     "DeliveryDate":"9/12"
    },
   {
     "SourceLocation":"England",
     "DestinationLocation":"Netherlands",
     "DeliveryDate":"12/12"
   }
]

The core idea here is to parse the JSON string to JArray’s and compare them.

public IEnumerable<String> CompareJsonArrays(string expected,string actual)
{
    // Parse string to JArrays
    JArray firstArray = JArray.Parse(expected);
    JArray secondArray = JArray.Parse(actual);

    // retrieve all children of JArray
    var firstTokens = firstArray.Children();
    var secondTokens = secondArray.Children();

    // Compare the two set of collections using Custom comparer
    var results = firstTokens.Except(secondTokens, new JTokenComparer())
                .Concat(secondTokens.Except(firstTokens,new JTokenComparer()));

    // Convert to Json String Representation
    return results.Select(x=>x.ToString());

}


Where JTokenComparer is defined as

public class JTokenComparer : IEqualityComparer<JToken>
{
    public int GetHashCode(JToken co)
    {
        return1;
    }

    public bool Equals(JToken x1, JToken x2)
    {
        if (object.ReferenceEquals(x1, x2))
        {
            return true;
        }
        if (object.ReferenceEquals(x1, null) ||
            object.ReferenceEquals(x2, null))
        {
            return false;
        }
        // Compares token and all child tokens.
        return JToken.DeepEquals(x1,x2);
    }
}

This would provide the difference in JSON string.

{
    "SourceLocation": "England",
    "DestinationLocation": "Netherlands",
    "DeliveryDate": "12/12"
}

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