MongoDB data access [C #]

We are about to start the simplest MongoDB connection to access data. Before that, you have installed MongoDB! Maybe, probably, it should have been installed. Really not installed yet? So: Click here to [install MongoDB]

Start:

Download a C # driver first. MongoDB provides development drivers for various mainstream and non-mainstream predictions.

C # DRIVER: click here

CSHARP driver Tutorial: click here

Download file installation or decompress package

If you are installing the package, go to the installation location. If you are using a zip package, extract the package and obtain the following two files:

1. MongoDB. bson. dll: serialization, JSON-related
2. MongoDB. Driver. dll: Our driver

No. Only these two files are our favorites.

 

Continue:

Create a C # project. Do you have vs2012 or vs2010? Send me a copy. Thanks for sharing :)

Add reference to introduce the above two DLL files to the Project

 

Have you started mongod.exe? What is it? Click here. Start the service.

 

CodeAdd a namespace:

Using MongoDB. bson;
Using MongoDB. driver;

Follow [CSHARP driver Tutorial: Click Here] to continue. If you do not open [CSHARP driver tutorial], do not open it. Read the full text to avoid distracting effort.

// MongoDB connection string, with [MongoDB: // . Here, we are connected to a local service
String Connectionstring =   " MongoDB: // localhost " ;
// Connect to a physical server
Mongoserver Server = Mongoserver. Create (connectionstring );

1. MongoDB connection string
   • In the connection string, we can specify the service and connection port formats on other machines as follows:
   • MongoDB: // [Username: password @] hostname [: Port] [/[database] [? Options]
   • Simple Example: MongoDB: // server1, server2: 27017, server2: 27018
   • For more details, refer to [CSHARP driver Tutorial: Click here]
2. Mongoserver
   • There are several different methods to create a reload:
   • External server create () If you only connect to the local machine and the local machine only starts one service, you can directly call this method without a connection string.
   • Mongoserver create (mongoonstringbuilder builder)
   • Login Server create (login url)
   • Login Server create (string connectionstring)
   • Login Server create (URI)
   • For more details, refer to [CSHARP driver Tutorial: Click here]

Continue:

Add several lines of code:

 

// MongoDB connection string, with [MongoDB: // . Here, we are connected to a local service
String Connectionstring =   " MongoDB: // localhost " ;
// Connect to a physical server
Mongoserver Server = Mongoserver. Create (connectionstring );
// -------------------------------------------------------------------------
// Open the database testdb
Analytic database DB = Server. getdatabase ( " Testdb " );
// Obtain the set employees
Mongocollection collection = DB. getcollection ( " Employees " );

1. Server. getdatabase ("Testdb")
   • Open the database: testdb
   • I don't have a database named testdb ?? Don't worry, don't worry, don't waste time on this issue, if you don't have this inventory, MongoDB will automatically create it for you
2. DB. getcollection ("Employees")
   • Get set: Employees
   • Well, with the previous lesson, do you care about him? If love does not exist, developers of MongoDB will create it for us?

Continue:

// MongoDB connection string, with [MongoDB: // . Here, we are connected to a local service
String Connectionstring =   " MongoDB: // localhost " ;
// Connect to a physical server
Mongoserver Server = Mongoserver. Create (connectionstring );
// -------------------------------------------------------------------------
// Open the database testdb
Analytic database DB = Server. getdatabase ( " Testdb " );
// Obtain the set employees
Mongocollection collection = DB. getcollection ( " Employees " ); // -------------------------------------------------------------------------
// Create an employee
Bsondocument employee =   New Bsondocument
{
{ " Name " , " Ernest Hemingway " },
{ " Title " , " For Whom the Bell Tolls " }
};
// Write it to the above set.
Collection. insert (employee );

If yourProgramIf no exception is thrown, the data already exists. I don't know what bsondocument is?

Let's look at a simple example:

Bsondocument document =NewBsondocument {
{"Name", Name },
{"City", City },// Not addedIfCity isNull
{"Dob", DOB, dobavailable}// Not addedIfDobavailable isFalse
};
It stores data in JSON format as a key-value pair. MongoDB uses bsondocument to set up bsondocument so that you can store data in complex formats.

• There are some important concepts.ArticleIn the future, you must go through bsontype, bsonvalue, bsonelement, bsondocument, server, database, and collection.
• Here: [CSHARP driver Tutorial: Click here]

Continue:

The last few lines of small code:

// -------------------------------------------------------------------------
// Query the data just inserted above. This format is used. Please refer to the querydocument document.
VaR Query =   New Querydocument ( " Name " , " Ernest Hemingway " );
// Traverse results
Foreach (Bsondocument EMP In Collection. Find (query ))
{
// Bsonvalue can be set to asxxx or toxxx.
Console. writeline ( " Name: {0} \ ttitle: {1} " , EMP [ " Name " ]. Asstring, EMP [ " Title " ]. Tostring ());
}

2. querydocument
   • collect collection books;
     var query = query. and (
     query. eq ( "author" , "Kurt Vonnegut" ),
     query. eq ( "title" , "Cats craddle" )
     );
   • I don't want to explain it. Please refer to the various documents for details of the query usage (because I haven't read it yet, I can't explain it, huh, huh ). As the first step, here we know that the accumulation of quantity and details has been continuously obtained in practice. [CSHARP driver Tutorial: Click Here]
4. Bsonvalue
   • EMP ["Name"]. AsstringThis is the first value method. Asint32, asboolean, etc.
   • EMP ["Title"]. Tostring() This is the second value method. Toint32, toboolean, etc.
   • Note the following details:
   • Asxxx value method. If the types are inconsistent, an invalidcastexception can be thrown.
   • Toxxx value method. If no exception is thrown, the default value is returned. [CSHARP driver Tutorial: Click here]

So far, you have completed the first access to MongoDB through the C # program. Other methods and details in development are an accumulation process. After taking the first step of success, I wish you a further step.

PS: It is finished.

I reiterate that important concepts:

Bsontype, bsonvalue, bsonelement, bsondocument, server, database, and collection

It depends on. [CSHARP driver Tutorial: Click here]