Question

我是JSON的新手，所以这可能是一个简单的问题。我有下面的代码（带有json对象，再次在下面）。

我只是希望能够读取JSON并将其中的项目放入变量中以便于读取。

我收到错误，这是由于返回的JSON对象中的文本ObjectID("")： Unexpected character encountered while parsing value: O. Path '_id', line 1, position 10.

从MONGO返回的JSON对象：

{
    "_id": ObjectId("543c2d426b6b5ef78b62fc41"),
    "LoanStatusAddedEvent": {
        "@From": "Lakewood",
        "@MessageTimeDateStamp": "2013-08-12T05:03:23.035-04:00",
        "@MessageID": "29055040",
        "LoanNumber": "5300494930",
        "CurrentIndicator": "true",
        "StatusChangeDate": "2013-08-11T20:01:01.000",
        "StatusValue": "42",
        "StatusType": "Active"
    }
}

代码：

        // connect to the mongo server and the Mongos DB
        string connectionString = "connectionstringhere";


        MongoServer mongo = MongoServer.Create(connectionString);
        mongo.Connect();

        MongoDatabase database = mongo.GetDatabase("Mangos");


        //Builds new Collection (looking at JsonImports on server)
        MongoCollection<LoanStatus> collection2 = database.GetCollection<LoanStatus>("JsonImports");


        var collection = database.GetCollection<BsonDocument>("JsonImports");


        var query = new QueryDocument(); //("LoanNumber", "5300494930");


        foreach (BsonDocument item in collection.Find(query))
        {
            string json = item.ToJson();

            Console.WriteLine(item);


            // code here to below http://james.newtonking.com/json/help/index.html?topic=html/QueryingLINQtoJSON.htm
            JObject rss = JObject.Parse(json);

            string rssLoanNumber = (string)rss["LoanStatusAddedEvent"]["LoanNumber"];

            Console.WriteLine(rssLoanNumber);



        }// end for each loop


        Console.WriteLine();
        Console.Read();


public class LoanStatus
{
    public string From { get; set; }

    public string MessageTimeDateStamp { get; set; }

    public string MessageID { get; set; }

    public string LoanNumber { get; set; }

    public string CurrentIndicator { get; set; }

    public string StatusChangeDate { get; set; }

    public string StatusValue { get; set; }

    public string StatusType { get; set; }

    //public string id { get; set; }



    public void PrintDetailsToScreen()
    {
        Console.WriteLine(String.Format("{0}{1}{2}",
                            this.LoanNumber, this.StatusChangeDate, this.StatusValue));
    }

}

public class RootObject
{
    public LoanStatus LoanStatus { get; set; }
}

Answer 1

您的对象应该有Field或Property，其名称为_id或Id，类型为ObjectId。

public ObjectId Id { get; set; }

如果您可以重新构建您的mongo数据库，则可以将Id的类型更改为String而不是ObjectId 并告诉mongo驱动程序将所有id视为字符串

BsonSerializer.RegisterIdGenerator(typeof(string), new StringObjectIdGenerator());

如果你这样做，你可以使用任何string作为Id，如果它为空，MongoDb会为你的文档创建一个随机Id

更新：

Mongodb Docuemnt不是有效的Json文档。它有一些不会用json.net解析的值。你应该手动删除它们。

有简单的代码

var json = "ObjectId(\"123\")";
var result =  Regex.Match(json, @"ObjectId\(([^\)]*)\)").Value;
var id = result.Replace("ObjectId(", string.Empty).Replace(")", String.Empty);
var validJson = json.Replace(result, id);

C＃从mongodb读取文档到JSON并尝试获取值

1 个答案: