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C# connection with MySQL Database

once again im not really getting any further by just using google and searching through the forum, so here we go:
Im trying to establish a connection with C# and a MySQL Database (which is running on phpmyadmin).
This is the Code I got so far:
using System;
using System.Data;
using MySql.Data.MySqlClient;
using MySql.Data;
namespace csharpdatabasefinal
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("C#: Connect to MySQL Database using localhost." + Environment.NewLine);
string connectionString = "server=localhost;user=csharptest;database=csharptest;port=3306;password=123";
MySqlConnection conn = new MySqlConnection(connectionString);
try
{
conn.Open();
Console.WriteLine("Connection is " + conn.State.ToString() + Environment.NewLine);
conn.Close();
Console.WriteLine("Connection is " + conn.State.ToString() + Environment.NewLine);
}catch(MySql.Data.MySqlClient.MySqlException ex)
{
Console.WriteLine("Error: " + ex.Message.ToString());
}
Console.WriteLine("Press any key to exit..");
Console.Read();
}
}
}
And this is the Error I get, I guess it has something to do with the References but im not really sure..
I added as reference "MySql.Data.dll" & "System.Security.Permissions.dll".
I added the Systen.Security.Permission.dll because in a previous error he asked for it.
And this is the Error I get:
Click me!(Error-Image)
Here the full Error Code:
System.TypeInitializationException
HResult=0x80131534
Message=The type initializer for 'MySql.Data.MySqlClient.Replication.ReplicationManager' threw an exception.
Source=MySql.Data
StackTrace:
at MySql.Data.MySqlClient.Replication.ReplicationManager.IsReplicationGroup(String groupName)
at MySql.Data.MySqlClient.MySqlConnection.Open()
at csharpdatabasefinal.Program.Main(String[] args) in C:\Users\anonym\source\repos\csharpdatabasefinal\csharpdatabasefinal\Program.cs:line 19
Inner Exception 1:
FileNotFoundException: Could not load file or assembly 'System.Configuration.ConfigurationManager, Version=4.0.3.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'. The system cannot find the file specified.

Enable "native code debugging" in Project -> Properties -> Debug
If that does't work, try adding the MySQL dll via nuget:
Install-Package MySql.Data -Version 8.0.20

csharp mysql compile error CS0246 under powershell

I am attempting to compile a simple C# program to do a select on one of the tables in the MySQL database on my windows 10 laptop. When I attempt to compile the code under Developer PowerShell for VS 2019 using the following command:
csc mysql1.cs
I get the error message error CS0246: The type or namespace name 'MySql' could not be found
I checked under the directory C:\Program Files (x86)\MySQL\MySQL Connector Net 8.0.18\Assemblies\v4.5.2 and I did indeed have the file MySql.Data.dll
All the articles I found with google stated that I had to "add a reference" to my project. I do not have a project, this is just a command line compile.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using MySql.Data.MySqlClient;
namespace ConsoleApp1
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("This is a MySQL Test");
string mysql_info = "Persist Security Info=False;server=localhost;database=myschema;uid=root;password=mypassword";
MySql.Data.MySqlClient.MySqlConnection dbConn =
new MySql.Data.MySqlClient.MySqlConnection(mysql_info);
MySqlCommand cmd = dbConn.CreateCommand();
cmd.CommandText = "SELECT user_id from hockey_users WHERE username ='someone'";
try
{
dbConn.Open();
} catch (Exception erro) {
MessageBox.Show("Error" + erro);
this.Close();
}
MySqlDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
idnumber = reader.ToString();
Console.WriteLine("id = " + idnumber);
}
}
}
}

How to connect to mysql with C# (simple program)

I am a beginner in C # and I intend to create a simple program to check the connection to the mysql server (in this case I am using xampp, so the connection is local).
The problem is that the connection to the mysql server does not work, so the "Can not open connection!" box pops up. I appreciate all the explanations. thank you :)
using System;
using System.Data;
using System.Data.SqlClient;
using System.Windows.Forms;
using MySql.Data.MySqlClient;
namespace WindowsFormsApp1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void btnSend_Click(object sender, EventArgs e)
{
SqlConnection cnn;
string server = "localhost";
string database = "test";
string uid = "root";
string password = ""; //im using xampp
string connectionString;
connectionString = "SERVER=" + server + ";" + "DATABASE=" +
database + ";" + "UID=" + uid + ";" + "PASSWORD=" + password + ";";
MySqlConnection connection = new MySqlConnection(connectionString);
cnn = new SqlConnection(connectionString);
try
{
cnn.Open();
MessageBox.Show("Connection Open ! ");
cnn.Close();
}
catch (Exception ex)
{
MessageBox.Show("Can not open connection ! ");
}
}
private void button1_Click(object sender, EventArgs e)
{
this.Close();
}
}
}

Thank you for clarifying the specific problem you're having. That's helpful ;)
Thank you, too, for posting the error message.
In the future, please copy/paste the error as TEXT, not an image.
In this case, it would have been nice to run the error text through Google Translate ;)
THE PROBLEM:
Based on the error message, it sounds like your C# program might be trying to use the SQL Server driver to talk to a MySQL database. That won't work :)
SUGGESTION:
Look at any of these links:
MySQL Connector/Net Developer Guide
MySQL C# tutorial
Connect C# to MySQL
At a minimum, you'll also need to get the MySQL driver (e.g. from NuGet):
how to get new mysql connector for c#

I have the same problem after a while i find out i can not use SqlConnection. SqlConnection is for SQL Server i need to install MySql.Data from NuGet:
Install-Package MySql.Data in your Package Manager Console
then i can create MySqlConnection object and connect to your database:
System.Data.IDbConnection cnn = new MySql.Data.MySqlClient.MySqlConnection("my Connection String");
try
{
cnn.Open();
MessageBox.Show("Connection Open ! ");
cnn.Close();
}

How can I create a SQL Server database file (.mdf) programmatically from C#?

I'm new to here. Recently I was ordered by my boss to make a SQL Server database from a Winforms app. I'm trying to create database programmatically. But every time I'm getting an error message.
Is it possible to create a SQL Server database file (.mdf) programmatically ?
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.SqlClient;
namespace mdf_creator
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void btnCreateDatabase_Click(object sender, EventArgs e)
{
String str;
SqlConnection myConn = new SqlConnection("Data Source =(LocalDB)\\MSSQLLocalDB; Integrated security =SSPI;database=master");
str = "CREATE DATABASE ss ON PRIMARY " +
"(NAME = ss_Data, " +
"FILENAME = 'D:\\ss.mdf', " +
"SIZE = 3MB, MAXSIZE = 10MB, FILEGROWTH = 10%) " +
"LOG ON (NAME = ss_Log, " +
"FILENAME = 'D:\\ss.ldf', " +
"SIZE = 1MB, " +
"MAXSIZE = 5MB, " +
"FILEGROWTH = 10%)";
SqlCommand myCommand = new SqlCommand(str, myConn);
try
{
myConn.Open();
myCommand.ExecuteNonQuery();
MessageBox.Show("DataBase is Created Successfully", "MyProgram", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
catch (System.Exception ex)
{
MessageBox.Show(ex.ToString(), "MyProgram",
MessageBoxButtons.OK, MessageBoxIcon.Information);
}
finally
{
if (myConn.State == ConnectionState.Open)
{
myConn.Close();
}
}
}
}
Where is the problem with my code?

The error message indicates that the SQL server was not able to create a file on the 'D:' drive. Make sure that the user the SQL server runs as has the necessary mappings and access rights to that drive.

Yes.
You can use SQL Server Managments Objects
//Connect to the local, default instance of SQL Server.
Server srv = new Server();
// Define a Database object variable by supplying the server and the
// database name arguments in the constructor.
Database db = new Database(srv, "Test_SMO_Database");
//Create the database on the instance of SQL Server.
db.Create();
//Reference the database and display the date when it was created.
db = srv.Databases["Test_SMO_Database"];
Console.WriteLine(db.CreateDate);

I would suggest firstly running Visual Studio as administrator. Right click the Visual Studio icon and 'Run as Administrator'.
I would also suggest implementing the answer here: How to request administrator permissions when the program starts?
This is so your application will require administrator access on the machine it is running on, which it will generally need if it is creating/deleting files.
Edit: If you still cannot access the drive when Visual Studio is running as administrator, then it is likely the Window's permissions on that drive, rather than any issue with your project.

System.Data.OleDb.OleDbException' occurred in System.Data.dll

Hey Members i am new to C# Language and Visual Studio Platform recently i am learning how to connect access Database with visual Studio and first time with same code i have connected with database but after some time when i compiled again then there is error given in Title.
why this is happening ?
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.OleDb;
namespace Clinic_Management_System
{
public partial class Login : Form
{
public Login()
{
InitializeComponent();
}
private void Login_Load(object sender, EventArgs e)
{
try
{
OleDbConnection connection = new OleDbConnection();
connection.ConnectionString = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users
\Hassan Gillani\Documents\Clinic Management System.accdb; Persist Security Info = False; ";
connection.Open();
label1.Text = "Connected to Clinic Management System Database";
connection.Close();
}
catch (Exception exp)
{
MessageBox.Show("Error " + exp);
}
}
}
}
please visit given like to view screen short
http://s33.postimg.org/5ltm4dtnj/Error.png

Using the verbatim character (#) and splitting your path in the middle in not a good idea.
Spaces counts in paths so the filename used for your connection is
C:\Users \Hassan Gillani\Documents\Clinic Management System.accdb;
If you try to use File.Exists on this string you get false as result.
Do not split your connection string in the middle of the path
connection.ConnectionString = #"Provider=Microsoft.ACE.OLEDB.12.0;
Data Source=C:\Users\Hassan Gillani\Documents\Clinic Management System.accdb;
Persist Security Info = False; ";