从 c# 动态构建 Yaml 文档

Question

是否可以使用 Yaml.DotNet 或其他库从 c# 动态构建 Yaml 文档？

我了解如何使用序列化来完成此操作，但这需要从对象结构开始。

我正在寻找一种方法来动态创建 Yaml 文档节点，就像使用 Xml 使用 XElement.Add(object) 方法一样。

Answer 1

您可以使用YamlDotNet 做到这一点。您首先创建一个YamlStream，向其中添加一个或多个document，然后您可以向其添加sequences、mappings 和scalars。

Here is an example on how to do it:

var address = new YamlMappingNode(
    new YamlScalarNode("street"),
    new YamlScalarNode("123 Tornado Alley\nSuite 16") { Style = YamlDotNet.Core.ScalarStyle.Literal },
    new YamlScalarNode("city"),
    new YamlScalarNode("East Westville"),
    new YamlScalarNode("state"),
    new YamlScalarNode("KS")
) { Anchor = "main-address" };

var stream = new YamlStream(
    new YamlDocument(
        new YamlMappingNode(
            new YamlScalarNode("repeipt"),
            new YamlScalarNode("Oz-Ware Purchase Invoice"),
            new YamlScalarNode("date"),
            new YamlScalarNode("2007-08-06"),
            new YamlScalarNode("customer"),
            new YamlMappingNode(
                new YamlScalarNode("given"),
                new YamlScalarNode("Dorothy"),
                new YamlScalarNode("family"),
                new YamlScalarNode("Gale")
            ),
            new YamlScalarNode("items"),
            new YamlSequenceNode(
                new YamlMappingNode(
                    new YamlScalarNode("part_no"),
                    new YamlScalarNode("A4786"),
                    new YamlScalarNode("descrip"),
                    new YamlScalarNode("Water Bucket (Filled)"),
                    new YamlScalarNode("price"),
                    new YamlScalarNode("1.47"),
                    new YamlScalarNode("quantity"),
                    new YamlScalarNode("4")
                ),
                new YamlMappingNode(
                    new YamlScalarNode("part_no"),
                    new YamlScalarNode("E1628"),
                    new YamlScalarNode("descrip"),
                    new YamlScalarNode("High Heeled \"Ruby\" Slippers"),
                    new YamlScalarNode("price"),
                    new YamlScalarNode("100.27"),
                    new YamlScalarNode("quantity"),
                    new YamlScalarNode("1")
                )
            ),
            new YamlScalarNode("bill-to"), address,
            new YamlScalarNode("ship-to"), address,
            new YamlScalarNode("specialDelivery"),
            new YamlScalarNode("Follow the Yellow Brick\n" +
                               "Road to the Emerald City.\n" +
                               "Pay no attention to the\n" +
                               "man behind the curtain.")
            {
                Style = YamlDotNet.Core.ScalarStyle.Literal
            }
        )
    )
);

Answer 2

我现在已经弄清楚了如何使用 Yaml.Net 来做到这一点。 YamlStream 需要使用 Load() 方法加载一些初始内容。

const string initialContent = "---\nversion: 1\n...";

var sr = new StringReader(initialContent);
var stream = new YamlStream();
stream.Load(sr);

然后您可以将 YamlDocument 的 RootNode 转换为具有 Add 方法的 YamlMappingNode。

var rootMappingNode = (YamlMappingNode)stream.Documents[0].RootNode;   
rootMappingNode.Add("shout", "yay!");

然后您可以在保存之前添加各种节点类型：

var props = new YamlMappingNode();
props.Add("prop1", "value1");
props.Add("prop2", "value2");
rootMappingNode.Add("itemWithProps", props);

var props2 = new YamlMappingNode();
props2.Add("prop1", "value1");
props2.Add("prop2", "value2");

var props3 = new YamlMappingNode();
props3.Add("prop1", "value1");
props3.Add("prop2", "value2");

var seq = new YamlSequenceNode();
seq.Add(props2);
seq.Add(props3);
rootMappingNode.Add("sequenceOfItems", seq);

var col = new YamlSequenceNode();
col.Style = SequenceStyle.Flow;
col.Add("a");
col.Add("b");
col.Add("c");

var seqMapping = new YamlMappingNode();
seqMapping.Add("collection", col);
seq.Add(seqMapping);

using (TextWriter writer = File.CreateText("C:\\temp\\test.yaml"))
    stream.Save(writer, false);

这个例子的输出是：

version: 1
shout: yay!
itemWithProps:
  prop1: value1
  prop2: value2
sequenceOfItems:
- prop1: value1
  prop2: value2
- prop1: value1
  prop2: value2
- collection: [a, b, c]
...

感谢 @Antoine Aubry 创建 Yaml.Net 并模糊地为我指明了正确的方向。