.NetFramework4.8实现读取yaml文件中父节点buildReleases下的releaseID节点值以及buildEnvironments下buildSystem的节点值

在.NET Framework 4.8中，你可以使用`System.IO.Pipelines.Text`库配合第三方库如`YamlDotNet`来解析YAML文件。首先，需要安装`YamlDotNet`库，可以通过NuGet包管理器添加。然后，以下是读取指定结构YAML文件内容的一个示例：

using System;
using System.IO.Pipelines.Text;
using YamlDotNet.Core;
using YamlDotNet.Readers;

class Program
{
    static void Main(string[] args)
    {
        string yamlFilePath = "path_to_your_yaml_file.yaml"; // 替换为实际文件路径

        using (FileStream stream = File.OpenRead(yamlFilePath))
        using (TextReader reader = new StreamReader(stream))
        {
            YamlDocument deserializer = new YamlDocument(new SingleLineParser(reader));

            if (deserializer.Documents.Count > 0)
            {
                var doc = deserializer.Documents[0];

                var buildReleases = doc.RootNode?.GetValue<Dictionary<string, object>>("buildReleases");
                if (buildReleases != null && buildReleases.TryGetValue("releaseID", out var releaseId))
                    Console.WriteLine($"Release ID: {releaseId}");

                var buildEnvironments = doc.RootNode?.GetValue<Dictionary<string, object>>("buildEnvironments")?.FirstOrDefault()?.GetValue<Dictionary<string, object>>("buildSystem");
                if (buildEnvironments != null && buildEnvironments.TryGetValue("name", out var buildSystemName))
                    Console.WriteLine($"Build System Name: {buildSystemName}");
            }
            else
            {
                Console.WriteLine("No documents found in the YAML file.");
            }
        }
    }
}

这段代码首先打开并读取YAML文件，然后使用`YamlDocument`类解析文件内容。接着，它尝试获取`buildReleases`和`buildEnvironments`下的相应节点，并打印出它们的值。

注意，上述代码假设`releaseID`和`buildSystem`都是字符串类型的。如果它们有不同的数据类型，你需要修改`GetValue`后的类型提示和相应的处理逻辑。