mongodb C#如何使用BSON文档 [英] mongodb c# how to work with BSON document
问题描述
我已经花了很多时间寻找答案... 这在PHP中非常简单,但我无法在C#中将其组合在一起(我是C#和mongo的新手.) 我正在尝试遍历存储文档的所有级别.该文档如下所示:
I've spent MANY hours looking for the answer... This is very easy in PHP but I just can't put it together in C#(I'm new to C# and mongo...) I'm trying to iterate through all levels of a stored document. The document looks like this:
{
"_id": ObjectId("51f90101853bd88971ecdf27"),
"fields": [
{
"ID": ObjectId("51fd09498b080ee40c00514e"),
"NAME": "ID",
"TYPE": "Text"
},
{
"ID": ObjectId("51fd09a68b080ee40c0064db"),
"NAME": "Title",
"TYPE": "Text"
},
{
"ID": ObjectId("51fd09b28b080ee40c004d31"),
"NAME": "Start Date",
"TYPE": "Date"
},
{
"ID": ObjectId("51fd09c28b080ee40c007f2e"),
"NAME": "Long Description",
"TYPE": "Memo"
}
],
"name": "TODB",
"updated": "Wed Jul 31 2013 08:20:17 GMT-0400 (Eastern Daylight Time)"
}
访问名称"和已更新"没有问题,但无法弄清楚如何访问字段"数组.
I have no problem accessing the "name" and "updated" but can't figure out how to access the "fields" array.
到目前为止的代码:
{
MongoServer mongo = MongoServer.Create();
mongo.Connect();
var db = mongo.GetDatabase("forms");
mongo.RequestStart(db);
var collection = db.GetCollection("forms");
var query = new QueryDocument("name",
"TODB");
mongo.Disconnect();
}
@foreach(BsonDocument item in collection.Find(query))
{
@item.GetElement("name").Value
@item.GetElement("_id").Value
}
同样,我可以访问名称和_id,但不能访问任何子文档值.
Again, I am able to access the name and _id just not any of the sub document values.
在此先感谢您的协助! 弄清楚阅读内容之后,我还将要写数据....
Thanks in advance for any assistance! After I get the reading figured out, I am also going to want to write data....
推荐答案
有几种方法,但这是一种:
There are a few ways, but here's one:
// build some test data
BsonArray dataFields = new BsonArray { new BsonDocument {
{ "ID" , ObjectId.GenerateNewId()}, { "NAME", "ID"}, {"TYPE", "Text"} } };
BsonDocument nested = new BsonDocument {
{ "name", "John Doe" },
{ "fields", dataFields },
{ "address", new BsonDocument {
{ "street", "123 Main St." },
{ "city", "Madison" },
{ "state", "WI" },
{ "zip", 53711}
}
}
};
// grab the address from the document,
// subdocs as a BsonDocument
var address = nested["address"].AsBsonDocument;
Console.WriteLine(address["city"].AsString);
// or, jump straight to the value ...
Console.WriteLine(nested["address"]["city"].AsString);
// loop through the fields array
var allFields = nested["fields"].AsBsonArray ;
foreach (var fields in allFields)
{
// grab a few of the fields:
Console.WriteLine("Name: {0}, Type: {1}",
fields["NAME"].AsString, fields["TYPE"].AsString);
}
您通常可以使用字符串索引器["name-of-property"]
遍历字段和子文档字段.然后,使用AsXYZ
属性将字段值转换为特定类型,如上所示.
You can often use the string indexer ["name-of-property"]
to walk through the fields and sub document fields. Then, using the AsXYZ
properties to cast the field value to a particular type as shown above.
这篇关于mongodb C#如何使用BSON文档的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!