Adding an item to a Dictionary using JsonPatch in ASP.NET Core

I have the following environment and version of .NET Core

.NET SDK (reflecting any global.json):   Version:   5.0.100   Commit:    5044b93829    Runtime Environment:   OS Name:     Mac OS X   OS Version:  11.0   OS Platform: Darwin   RID:         osx.11.0-x64   Base Path:   /usr/local/share/dotnet/sdk/5.0.100/  

Using the following code and endpoint.

public class Trie  {      public string Id { get; set; }        public Dictionary<string, TrieNode> Nodes { get; set; }  }    public class TrieNode  {      public string Name { get; set; }  }  

public async Task<IActionResult> Patch(string id, [FromBody] JsonPatchDocument<Trie> patchDoc)  {      var trie = [get from database]      patchDoc.ApplyTo(trie, ModelState);  }  

When I use the following op:

[    {      "op": "add",      "path": "/nodes/-", "value": { "/": { "name": "hello, world" } }    }  ]  

an item is added to the dictionary like this:

"Nodes": {      "-": {          "Name": null      }  }  

If I use the following syntax for the op

[    {      "op": "add",      "path": "/nodes", "value": { "/": { "name": "hello, world" } }    }  ]  

The item is added like this:

"Nodes": {      "/": {          "Name": "hello, world"      }  }  

But when I try to add a new item with another key like this:

[    {      "op": "add",      "path": "/nodes", "value": { "/my-key": { "name": "hello, world" } }    }  ]  

The item is not added, it's replaces the first entry so the result looks like this:

"Nodes": {      "/my-key": {          "Name": "hello, world"      }  }  

How can I add, remove, replace, copy, move entries in a Dictionary<string, TrieNode>?

https://stackoverflow.com/questions/66723977/adding-an-item-to-a-dictionary-using-jsonpatch-in-asp-net-core March 21, 2021 at 12:33AM