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c#.netjson.netjsonpath

Json.NET SelectTokens not working if json contains empty array


I have a valid JSON object that contains multiple "en-US" keys, which I'm trying select. For that purpose I use the JsonPath

"$..en-US"

which is given to the SelectTokens procedure implemented by the Json.NET. It's a JSON framework for .NET . Everything is working fine and well as long as my JSON doesn't contain any empty array. Here's an example:

var myJsonPath = "$..en-US";
var myJson = 
        @"{
            'controls': [
                {
                    'messages': {
                        'addSuggestion': {
                            'en-US': 'Add'
                        }
                    }
                },
                {
                    'header': {
                        'controls': []
                    },
                    'controls': [
                        {
                            'controls': [
                                {
                                    'defaultCaption': {
                                        'en-US': 'Sort by'
                                    },
                                    'sortOptions': [
                                        {
                                            'label': {
                                                'en-US': 'Name'
                                            }
                                        }
                                    ]
                                }
                            ]
                        }
                    ]
                }
            ]
        }";
var jToken = JObject.Parse(myJson);
var tokens = jToken.SelectTokens(myJsonPath);

Here, the tokens variable will contain just one element! That will be the "en-US" occurence BEFORE the empty array in the 'controls' of the 'header' object. However, when I just leave this 'header' object out:

var myJson = 
    @"{
        'controls': [
            {
                'messages': {
                    'addSuggestion': {
                        'en-US': 'Add'
                    }
                }
            },
            {
                'controls': [
                    {
                        'controls': [
                            {
                                'defaultCaption': {
                                    'en-US': 'Sort by'
                                },
                                'sortOptions': [
                                    {
                                        'label': {
                                            'en-US': 'Name'
                                        }
                                    }
                                ]
                            }
                        ]
                    }
                ]
            }
        ]
    }";

I will get all the 3 occurencies of the "en-US" as expected. Btw, if I validate my JsonPath on the first JSON object (i.e. which contains an empty array) in an online tool, then as expected, I get all the three "en-US" cases. This diverges from what I'm getting from the Json.NET. I'm wondering whether it's a bug or do I have to handle this case manually somehow?


Solution

  • This is a bug that has been fixed. Upgrade to the latest version of Json.NET.