Seeking guidance reading .yaml files with C#

Question

Two months later: The YAML (Eve Online blueprint.yaml) file I tried to parse changed a huge deal which also made it much easier to parse using de deserializer. If someone (f

Answer 1

You have too much stuff going on in one line of code. Create a new YamlScalarNode object in one line, access the array in another line, cast the resultant object in another line. That way, you'll narrow down the problem area to a single step.

The message is telling you that you are retrieving a YamlMappingNode from the array but you are casting it to a YamlSequenceNode. Which is not allowed since the two types are obviously not related.

Answer 2

Your question has already been correctly answered, but I would like to point out that your approach is probably not the best one for parsing files. The YamlDotNet.RepresentationModel.* types offer an object model that directly represents the YAML stream and its various parts. This is useful if you are creating an application that processes or generates YAML streams.

When you want to read a YAML document into an object graph, the best approach is to use the Deserializer class. With it you can write your code as follows:

using(var reader = File.OpenText("blueprints.yaml")
{
    var deserializer = new Deserializer();
    var blueprintsById = deserializer.Deserialize<Dictionary<int, YamlBlueprint>>(reader);

    // Use the blueprintsById variable
}

The only difference is that the Id property of the YamlBlueprint instances won't be set, but that's just a matter of adding this:

foreach(var entry in blueprintsById)
{
    entry.Value.Id = entry.Key;
}

Answer 3

Well that was kinda stupid... it's kind of hard to create an mapping of something which only contains one element. I've edited the repo linked in the OP with an working example in case somebody runs into the same problem.