Modify content without affective comments and other using YamlDotnet in C#

Question

Can anyone help me. I'm trying to modify the yaml config.

This is the sample yaml:

person:
    # some comments
    name: "Test"
    # some comments
    age: 20

I want to modify only the age without affecting like comments and other infos. And then save it again to file.

But in my trial, the comments is not being save but only the deserialized data.

Thank you.

Possible duplicate of https://stackoverflow.com/questions/63966877/how-to-preserve-the-comments-when-parsing-yaml-stream-in-c — Jay Buckman, Feb 10 '23 at 14:38

score -1 · Accepted Answer · answered Feb 10 '23 at 16:36

using YamlDotNet.Core;
using YamlDotNet.Core.Events;

using var reader = new StreamReader("test.yaml");

var scanner = new Scanner(reader, skipComments: false);
var parser = new Parser(scanner);

//using var writer = new StreamWriter("test2.yaml");
//var emitter = new Emitter(writer);
var emitter = new Emitter(Console.Out);

while (parser.MoveNext())
{
    if (parser.Current is Scalar scalar)
    {
        if (scalar.IsKey && scalar.Value == "age")
        {
            emitter.Emit(scalar);

            parser.MoveNext(); // move to age value

            emitter.Emit(new Scalar("30")); // new age value
            continue;
        }
    }
    emitter.Emit(parser.Current);
}

It almost works. The following result is obtained:

person
# some comments
:
  name: "Test"
  # some comments
  age: 30

The emitter violates the output. A colon is placed after the comment.

Do further research yourself.

Thank you so much. I'm going to try it later and will give feedback — Maherz123, Feb 10 '23 at 21:55

Modify content without affective comments and other using YamlDotnet in C#

1 Answers1