如何以遞歸方式在對象子級列表中找到所有對象？

Question

我有一個需要處理的對象。 此對象的類型為SchemaValidationResults ，其中包含列表List<SchemaValidationResults> NestedResults ，該List<SchemaValidationResults> NestedResults可能包含也可能不包含其他SchemaValidationResults對象。

為了更清楚地說明這一點，我在下面提供了JSON表示形式。 在此JSON表示中包含一個父對象，該父對象包含一個子對象，該子對象具有兩個子對象。 這些子對象之一具有另一個子對象。

因此，我們有：

Parent
     Child
          Child
          Child
               Child

我需要能夠在此JSON表示形式中檢索沒有任何其他子代的對象。 因此，在上述結構中，我需要這兩個孩子。

Parent
     Child
          Child <-- Need
          Child
               Child <- Need

JSON格式

{
  "valid": false,
  "keywordLocation": "#/properties/form_submission/properties/sections/properties",
  "instanceLocation": "#/form_submission/sections",
  "keyword": "properties",
  "errors": [
    {
      "valid": false,
      "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions",
      "instanceLocation": "#/form_submission/sections/6/questions",
      "errors": [
        {
          "valid": false,
          "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions/properties/102/$ref/properties/answer/type",
          "instanceLocation": "#/form_submission/sections/6/questions/102/answer",
          "keyword": "type",
          "additionalInfo": {
            "expected": "string",
            "actual": "number"
          }
        },
        {
          "valid": false,
          "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions/allOf",
          "instanceLocation": "#/form_submission/sections/6/questions",
          "keyword": "allOf",
          "errors": [
            {
              "valid": false,
              "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions/allOf/0/else/properties/100/properties/answer/maxLength",
              "instanceLocation": "#/form_submission/sections/6/questions/100/answer",
              "keyword": "maxLength",
              "additionalInfo": {
                "expected": 0,
                "actual": 2
              }
            }
          ]
        }
      ]
    }
  ]
}

這種性質使我相信遞歸將能夠幫助我創建一個沒有更多子代的所有子代對象的列表。

但是，我開始寫一個方法，我很快意識到我不確定如何構造該方法以實現所需的結果。 到目前為止，我有這個：

public List<SchemaValidationResults> GetChildLessError(SchemaValidationResults errors)
        {
            List<SchemaValidationResults> childLessErrors = new List<SchemaValidationResults>();

            foreach(var result in errors.NestedResults)
            {
                if(result.NestedResults.Count == 0)
                {
                    childLessErrors.Add(result);
                }
                else
                {
                    foreach(var resultChild in result.NestedResults)
                    childLessErrors.AddRange(GetChildLessError(resultChild));
                }
            }

            return childLessErrors;
        }

這種方法很有效，它產生的對象列表中沒有任何子對象，但是我所期望的10個對象中，只有6個對象。

下面是我正在運行此方法的完整JSON文件。 第一個JSON文件只是一個片段。

{
  "valid": false,
  "keywordLocation": "#/properties/form_submission/properties/sections/properties",
  "instanceLocation": "#/form_submission/sections",
  "keyword": "properties",
  "errors": [
    {
      "valid": false,
      "keywordLocation": "#/properties/form_submission/properties/sections/properties/1/properties/questions/properties/3/$ref/properties/answer/enum",
      "instanceLocation": "#/form_submission/sections/1/questions/3/answer",
      "keyword": "enum"
    },
    {
      "valid": false,
      "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions",
      "instanceLocation": "#/form_submission/sections/6/questions",
      "errors": [
        {
          "valid": false,
          "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions/properties/102/$ref/properties/answer/type",
          "instanceLocation": "#/form_submission/sections/6/questions/102/answer",
          "keyword": "type",
          "additionalInfo": {
            "expected": "string",
            "actual": "number"
          }
        },
        {
          "valid": false,
          "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions/allOf",
          "instanceLocation": "#/form_submission/sections/6/questions",
          "keyword": "allOf",
          "errors": [
            {
              "valid": false,
              "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions/allOf/0/else/properties/100/properties/answer/maxLength",
              "instanceLocation": "#/form_submission/sections/6/questions/100/answer",
              "keyword": "maxLength",
              "additionalInfo": {
                "expected": 0,
                "actual": 2
              }
            },
            {
              "valid": false,
              "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions/allOf/1/else/properties/101/properties/answer/maxLength",
              "instanceLocation": "#/form_submission/sections/6/questions/101/answer",
              "keyword": "maxLength",
              "additionalInfo": {
                "expected": 0,
                "actual": 3
              }
            },
            {
              "valid": false,
              "keywordLocation": "#/properties/form_submission/properties/sections/properties/6/properties/questions/allOf/4/else/properties/104/properties/answer/maxLength",
              "instanceLocation": "#/form_submission/sections/6/questions/104/answer",
              "keyword": "maxLength",
              "additionalInfo": {
                "expected": 0,
                "actual": 5
              }
            }
          ]
        }
      ]
    },
    {
      "valid": false,
      "keywordLocation": "#/properties/form_submission/properties/sections/properties/8/properties/questions",
      "instanceLocation": "#/form_submission/sections/8/questions",
      "errors": [
        {
          "valid": false,
          "keywordLocation": "#/properties/form_submission/properties/sections/properties/8/properties/questions/properties/191/$ref/properties/answer",
          "instanceLocation": "#/form_submission/sections/8/questions/191/answer",
          "errors": [
            {
              "valid": false,
              "keywordLocation": "#/properties/form_submission/properties/sections/properties/8/properties/questions/properties/191/$ref/properties/answer/minLength",
              "instanceLocation": "#/form_submission/sections/8/questions/191/answer",
              "keyword": "minLength",
              "additionalInfo": {
                "expected": 1,
                "actual": 0
              }
            },
            {
              "valid": false,
              "keywordLocation": "#/properties/form_submission/properties/sections/properties/8/properties/questions/properties/191/$ref/properties/answer/enum",
              "instanceLocation": "#/form_submission/sections/8/questions/191/answer",
              "keyword": "enum"
            }
          ]
        },
        {
          "valid": false,
          "keywordLocation": "#/properties/form_submission/properties/sections/properties/8/properties/questions/allOf/12/else/properties/191/properties/answer/enum",
          "instanceLocation": "#/form_submission/sections/8/questions/191/answer",
          "keyword": "enum"
        }
      ]
    },
    {
      "valid": false,
      "keywordLocation": "#/properties/form_submission/properties/sections/properties/9/properties/questions/allOf",
      "instanceLocation": "#/form_submission/sections/9/questions",
      "keyword": "allOf",
      "errors": [
        {
          "valid": false,
          "keywordLocation": "#/properties/form_submission/properties/sections/properties/9/properties/questions/allOf/0/else/properties/211/properties/answer/maxLength",
          "instanceLocation": "#/form_submission/sections/9/questions/211/answer",
          "keyword": "maxLength",
          "additionalInfo": {
            "expected": 0,
            "actual": 12
          }
        },
        {
          "valid": false,
          "keywordLocation": "#/properties/form_submission/properties/sections/properties/9/properties/questions/allOf/1/else/properties/240/properties/answer/maxLength",
          "instanceLocation": "#/form_submission/sections/9/questions/240/answer",
          "keyword": "maxLength",
          "additionalInfo": {
            "expected": 0,
            "actual": 4
          }
        }
      ]
    }
  ]
}

Answer 1

您的一個循環太多。

這是您代碼的修訂版：

public List<SchemaValidationResults> GetChildLessError(SchemaValidationResults errors)
{
    List<SchemaValidationResults> childLessErrors = new List<SchemaValidationResults>();

    if(errors.NestedResults.Any())
    {
        foreach(var resultChild in errors.NestedResults)
        {
            childLessErrors.AddRange(GetChildLessError(resultChild));
        }
    }
    else
    {
        childLessErrors.Add(errors);                    
    }
    return childLessErrors;
}