Question

我正在研究一个测试用例来模拟我的C＃方法。我无法使用令牌[＆＃34; DocumentID＆＃34;] 访问JToken的DocumentID属性。我收到System.InvalidOperationException - ＆＃34;无法访问Newtonsoft.Json.Linq.JValue＆＃34;上的子值。

string response = "[\r\n  \"{ \\\"DocumentID\\\": \\\"fakeGuid1\\\",\\\"documentNotes\\\": \\\"TestNotes1\\\"}\"\r\n]";
//Response has escape charaters as  this is being returned by a mockMethod which is supposed to return JSon.ToString().

string[] fakeGuidForExecutiveSummary = new string[]{"fakeGuid1"};
string fakeResponseFromExecutiveSummaryProxy = "{ \"DocumentID\": \"fakeGuid1\",\"documentNotes\": \"TestNotes1\"}";

JArray jsonResponse = JArray.Parse(response);
//Value of jsonResponse from Debugger - {[  "{ \"DocumentID\": "fakeGuid1\",\"documentNotes\": \"TestNotes1\"}" ]}

JToken token = jsonResponse[0];
//Value of token from Debugger - { "DocumentID": fakeGuid1","documentNotes": "TestNotes1"}
Assert.AreEqual(fakeGuidForExecutiveSummary[0], token["DocumentID"]);

Answer 1

您无法显示初始化fakeGuidForExecutiveSummary的方式。假设您通过以下方式执行此操作：

        string fakeResponseFromExecutiveSummaryProxy = "{ \"DocumentID\": \"fakeGuid1\",\"documentNotes\": \"TestNotes1\"}";
        var fakeResponse = JToken.Parse(fakeResponseFromExecutiveSummaryProxy);
        var fakeGuidForExecutiveSummary = fakeResponse["DocumentID"];

然后问题是fakeGuidForExecutiveSummary是JValue，而不是JToken或JArray。如果您尝试按索引访问（不存在的）子值，则您的代码将抛出您看到的异常。

相反，您需要执行以下操作：

        string response = @"[{ ""DocumentID"": ""fakeGuid1"",""documentNotes"": ""TestNotes1""}]";
        JArray jsonResponse = JArray.Parse(response);
        JToken token = jsonResponse[0];

        //Value of token from Debugger - { "DocumentID": fakeGuid1","documentNotes": "TestNotes1"}
        Assert.AreEqual(fakeGuidForExecutiveSummary, token["DocumentID"])

<强>更新

鉴于您更新的代码，问题在于您的示例JSON response包含太多级别的字符串转义：\\\"DocumentID\\\"。您可能将Visual Studio中显示的转义字符串复制到源代码中，然后再将它们转义一次。

将其更改为

        string response = "[\r\n  { \"DocumentID\": \"fakeGuid1\",\"documentNotes\": \"TestNotes1\"}\r\n]";

访问JToken值时获取异常 - 无法访问Newtonsoft.Json.Linq.JValue上的子值

1 个答案: