Search code examples
c#json.net

JArray.Contains issue


I have a JArray, read from a file :

private void RemoveCatalog(Catalog catalog) {

    System.IO.StreamReader filereader = new System.IO.StreamReader(@appDirectory + "\\list");

    JArray myjarray = JArray.Parse(filereader.ReadToEnd());
    filereader.Close(); 

    string json = " {\"token\":\"" + catalog.Token + "\",\"name\":\"" + catalog.Name +"\",\"logo\":\"" + catalog.Logo + "\",\"theme\":\"" + catalog.Theme + "\"}";

    JObject myCatalogAsJObject = JObject.Parse(json);

    myjarray.Remove(myCatalogAsJObject);

}

I want to remove the JObject corresponding to myCatalogAsJObject variable, but it doesn't work, because the answer of myjarray.Contains(myCatalogAsJObject) is false.

The problem is that myjarray actually contains it : it's the only JObject in my JArray.

If I do myCatalogAsJObject.ToString().Equals(myjarray.First.ToString()), the answer is true however.

I'm stuck.


Solution

  • .Contains (and .Remove) by default will compare references. Since you're creating a new JObject, the array does not contain that instance.

    You could get the instance of the object from the array and remove that:

    JObject match = myjarray.FirstOrDefault(j => j.token == catalog.token &&
                                                 j.name  == catalog.name  &&
                                                 j.logo  == catalog.logo  &&
                                                 j.theme == catalog.theme);
    
    myjarray.Remove(match);
    

    EDIT : Here is your code, simplified :

    JToken match = myjarray.FirstOrDefault(j => j.ToString().Equals(myCatalogAsJObject.ToString()));
    
    myjarray.Remove(match);