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C# Mysql login error

I am working with C# (visual studio 2012 professional) and Mysql . I trying to create a login form, where a user needs to insert the username and password:
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 MySql.Data.MySqlClient;
namespace Dark_Heresy
{
public partial class Login_Menu : Form
{
private MySqlConnection connection = new MySqlConnection();
public Login_Menu()
{
InitializeComponent();
TextPassword.PasswordChar = '*';
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void btn_Login_Click(object sender, EventArgs e)
{
try
{
string connectionString = "datasource = localhost; port = 3306; username = root; password = Mypass;";
using(MySqlConnection myConn = new MySqlConnection(connectionString))
using(MySqlCommand selectCommand = new MySqlCommand())
{
selectCommand.CommandText = ("SELECT COUNT(1) FROM dark_heresy.users WHERE users_=#User and password_=#Password;");
selectCommand.Connection = myConn;
selectCommand.Parameters.Add(new MySqlParameter("User", MySqlDbType.VarChar).Value = TextUserName.Text);
selectCommand.Parameters.Add(new MySqlParameter("Password", MySqlDbType.VarChar).Value = TextPassword.Text);
myConn.Open();
var ret = selectCommand.ExecuteScalar();
var count = Convert.ToInt32(ret);
if (count == 1)
{
this.Hide();
Menu mn = new Menu();
mn.ShowDialog();
}
else if (count > 1)
{
MessageBox.Show("Duplication of Username and Password... Access Denied");
}
else
{
MessageBox.Show("Incorrect Username and/or Password");
}
}
}
catch (Exception exp)
{
MessageBox.Show("Error: \r\n" + exp);
}
}
}
}
I don't get any syntax errors, but when i run this code i recieve this error:
MySql.Data.MySqlClient.MySqlException(0x80004005):
Only MySqlParameter objects may be stored at MySql.Data.MySqlClient.MySqlParameterCollection.Add(Object value)
at Dark_Heresy.Login_Menu.btn_Login_Click(Object sender, EventArgs e)
I know for security reason is it a better idea to use mysql.user table instead of dark_heresy.users table for user check, but right now is for testing purpose.
What is wrong with the code?
it says there is an error in line 39

I think your parameter syntax is wrong.
= operator returns the right side value also instead of just assigning. That's why;
new MySqlParameter("User", MySqlDbType.VarChar).Value = TextUserName.Text;
expression returns TextUserName.Text as a value and your parameter part will be like;
selectCommand.Parameters.Add(TextUserName.Text);
The right syntax seems;
selectCommand.Parameters.Add("#User", MySqlDbType.VarChar).Value = TextUserName.Text;
selectCommand.Parameters.Add("#Password", MySqlDbType.VarChar).Value = TextPassword.Text;
And please, don't store your passwords as a plain text.
Read: Best way to store password in database

connecting to database - connectionString connect.Open() error

So I am trying to run a query in a database that searches the database table from a textbox input. My code is
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 Query
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void employeeBindingNavigatorSaveItem_Click(object sender, EventArgs e)
{
this.Validate();
this.employeeBindingSource.EndEdit();
this.tableAdapterManager.UpdateAll(this.personnelDataSet);
}
private void Form1_Load(object sender, EventArgs e)
{
// TODO: This line of code loads data into the 'personnelDataSet.employee' table. You can move, or remove it, as needed.
this.employeeTableAdapter.Fill(this.personnelDataSet.employee);
}
private void btnExit_Click(object sender, EventArgs e)
{
this.Close();
}
string connectionString = "Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;";
private void btnSearch_Click(object sender, EventArgs e)
{
string commandText = "SELECT employeeID, name, position, hourlyPayRate " +
"FROM dbo.employee WHERE name LIKE '%'+ #Name + '%'";
using (SqlConnection connection = new SqlConnection(connectionString))
{
//Create a SqlCommand instance
SqlCommand command = new SqlCommand(commandText, connection);
//Add the parameter
command.Parameters.Add("#Name", SqlDbType.VarChar, 20).Value = textBox1.Text;
//Execute the query
try
{
connection.Open();
command.ExecuteNonQuery();
}
catch
{
//Handle excepetion, show message to user...
MessageBox.Show("Error bitch!");
}
finally
{
connection.Close();
}
}
}
}
}
When I take the catch out I can see the error occurs at connection.Open(). The error takes a while to happen which makes me wonder whether there is an issue with string connectionString = "Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;";
This is the error that I receive:
An unhandled exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll

You need to validate the connection string. If Open() is throwing an SqlException then the connection string is invalid. To enable you to establish the exact form of the connection string you require, take a look at connectionstrings.com.
As to why the exception is showing as unhanded, you need to 'consume' the exception as follows:
try
{
connection.Open();
command.ExecuteNonQuery();
}
catch (Exception e)
{
// Handle excepetion, show message to user...
MessageBox.Show(e.Message);
}
I hope this helps.

Check this out:
string connectionString = "Server=.\InstanceName;Database=myDataBase;Integrated Security=True;";
Also
string commandText = "SELECT employeeID, name, position, hourlyPayRate
FROM dbo.employee WHERE name LIKE '%#Name%'";

try:
string connectionString = "Data Source=myServerAddress;Initial Catalog=myDataBase;User id=myUser;Password=myPAss;Connect Timeout=15;Integrated Security=false";

Try declaring your connection string inside the event.
An alternate method is to link your database through web.config as follows:
<connectionStrings>
<connectionString="Data Source=(localdb)\v11.0;Initial Catalog=DBName;Integrated Security=True" providerName="System.Data.SqlClient"/>
</connectionStrings>
And then the connection string can be as:
string cs = ConfigurationManager.ConnectionStrings["DBName"].ConnectionString;

how to connect to localhost with this code?

i have a problem with this c# code. I need to connect it to mysql, localhost database, Please give me the correct code to [connetionString = "Data Source=ServerName;Initial Catalog=root;User ID=root;Password="; ] connect to the localhost.
using System;
using System.Windows.Forms;
using System.Data.SqlClient;
namespace WindowsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
string connetionString = null;
SqlConnection cnn ;
**connetionString = "Data Source=ServerName;Initial Catalog=localhost;User ID=root;Password=";**
cnn = new SqlConnection(connetionString);
try
{
cnn.Open();
MessageBox.Show ("Connection Open ! ");
cnn.Close();
}
catch (Exception ex)
{
MessageBox.Show("Can not open connection ! ");
}
}
}
}

It should look a little more like this:
connetionString = "Data Source=localhost;Initial Catalog=<Name of the Database>;User ID=root;Password=";
The data source property is where you put the network location, the initial catalog is the name of the database (in mysql).
Edit:
However, I believe you'll need the mysql libraries, which I notice you're not using at the beginning.
Get them from here: http://dev.mysql.com/downloads/connector/net/
The Data.SqlClient namespace is typically how you'd connect to MSSQL.

it seems you have tagged MySql connection, so preferably you want to use the mysql connection. Which you can download / install here: http://dev.mysql.com/downloads/connector/net/
Also it is wise to use the try-catch-finally approach. So that when the connection opens, and some exception occurs, the connection will always close afterwards.
As another addition, you could put the connectionstring in an App.Config or Web.Config so that you have the connectionstring available in all your files, and only have to adjust it in one place.
hope this will help you
using System;
using System.Windows.Forms;
using MySql.Data.MySqlClient; //using the mysql dll
namespace WindowsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
string connectionString = "Data Source=localhost;Initial Catalog=myDb;User ID=MyUser;Password=MyPass";
MySqlConnection cnn = new MySqlConnection(connectionString);
try
{
cnn.Open();
MessageBox.Show("Connection Open ! ");
}
catch (Exception ex)
{
MessageBox.Show("Can not open connection ! ");
MessageBox.Show(ex.Message); //shows what error actually occurs
}
finally
{
cnn.Close();
}
}
}
}

You are using System.Data.SqlClient in your connection which I think used for SQL Server. Your connection string is also not for MySQL Database. Try this one.
using System.Data.Odbc;
string connectionString = "DRIVER={MySQL ODBC 5.1 Driver}; SERVER=localhost;
DATABASE=dbname; UID=myuserid; PASSWORD=mypassword;OPTION=3; POOLING=false;";
OdbcConnection DBCon = new OdbcConnection(connectionString);
if (DBCon.State == ConnectionState.Open)
{
DBCon.Close();
}
DBCon.Open();
MessageBox.Show ("Connection Open ! ");
DBCon.Close();
Change the ODBC Driver version depending on what you are using.
Change the DATABASE, UID and PASSWORD value.

Here is the code you need
private void btnConnect_Click(object sender, EventArgs e)
{
string MyConStr = "Server=localhost;Database=YourDB;Username=YourUsername;Password=YourPassword";
MySqlConnection conn = new MySqlConnection(MyConStr);
conn.Open();
if (conn.State == ConnectionState.Open)
{
MessageBox.Show("Connection Opened Successfully");
conn.Close();
}
else
{
MessageBox.Show("Error Connecting to DataBase");
}
}

Edit database in management studio using visual studio c#

I have created a database using SQL Server Management Studio and am now trying to edit that database using Visual Studio Express 2012. I have connected the database to Visual Studio and can see my database but I have not been able to edit the database stored in Management Studio using Visual Studio. I have created a form and am trying to insert what is entered into textbox1 into a specific cell on my database after the user defines the column name and row (using the primary key in my DB) with textbox2 and textbox3. What code can I use to perform this action? So far I have had no luck. Thank you in advance for you help.
This is my current code:
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;
using System.Data.Sql;
using Microsoft.SqlServer.Server;
using System.Data.Linq;
using System.Data.Linq.Mapping;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
SqlConnection myConnectionString = new SqlConnection("Data Source=Server Catalog=DataBase;Integrated Security=True");
SqlCommand command = new SqlCommand();
private void maskedTextBox1_MaskInputRejected(object sender, MaskInputRejectedEventArgs e)
{
}
private void button3_Click(object sender, EventArgs e)
{
try
{
using (SqlConnection dbConnection = new SqlConnection()) // the "using" construct will close and dispose of the connection
{
dbConnection.ConnectionString = ("Data Source=Server ;Initial Catalog=Database;Integrated Security=True");
dbConnection.Open();
maskedTextBox1.Clear();
dateTimePicker1.Value = DateTime.Now.AddDays(0);
comboBox1.SelectedIndex = -1;
String username = comboBox2.Text;
using (SqlCommand command = new SqlCommand("INSERT INTO [Table Name] (Column Name) VALUES ([Parm1])", dbConnection))
{
command.Parameters.AddWithValue("Parm1", username);
command.ExecuteNonQuery();
}
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
private void button1_Click(object sender, EventArgs e)
{
this.Close();
}
private void button2_Click(object sender, EventArgs e)
{
//Close the Window
this.Close();
}
private void label4_Click(object sender, EventArgs e)
{
}
private void comboBox1_DataSourceChanged(object sender, EventArgs e)
{
}
private void button4_Click(object sender, EventArgs e)
{
myConnectionString.Open();
MessageBox.Show("Sql is connected");
myConnectionString.Close();
}
}
}

The VALUES clause should specify a parameter and that parameter should be specified when adding the parameter value. Try substituting the following:
String sqlquery = "INSERT INTO [Man Power] ([Person_Performing_Phase_2]) VALUES ([Parm1])";
SqlCommand command = new SqlCommand(sqlquery, con);
command.Parameters.AddWithValue("Parm1", username);
EDIT
Your connection string is incorrectly formed. I believe the following format is appropriate for your current needs:
String myConnectionString = Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;
I would use the following code for inserting data, which opens and closes the connection for each operation. Note the "command.ExecuteNonQuery" statement - its omission is why your insert failed to work - although I am unsure why opening the connection did not throw an error.
private void button3_Click(object sender, EventArgs e)
{
try
{
using (SqlConnection dbConnection = new SqlConnection()) // the "using" construct will close and dispose of the connection
{
dbConnection.ConnectionString = myConnectionString;
dbConnection.Open();
maskedTextBox1.Clear();
dateTimePicker1.Value = DateTime.Now.AddDays(0);
comboBox1.SelectedIndex = -1;
String username = comboBox2.Text;
using (SqlCommand command = new SqlCommand("INSERT INTO [Man Power] ([Person_Performing_Phase_2]) VALUES ([Parm1])", dbConnection))
{
command.Parameters.AddWithValue("Parm1", username);
command.ExecuteNonQuery();
}
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
You should also remove all other _Click methods and replace the connection and command statement with the myConnectionString assignement.

restriction error on messages between SQLSERVER and dot.net

Update:
I tried to run this on a local instance of sql-server and sadly it worked!!!
now I know that the code is right and there is some kind of DBA restriction I need to find (and ask the DBA to remove)
Any ideas?
using System;
using System.Collections.Generic;
using System.Text;
using System.Data.SqlClient;
using System.Data;
namespace testDBMessages
{
public class CGeneral
{
// Declare and instantiate connection
private static Form1 caller;
public CGeneral(Form1 caller1)
{
caller = caller1;
string connString = "server=(local)\\SQLEXPRESS;database=tests;Integrated Security=SSPI";
SqlConnection cn = new SqlConnection(connString);
cn.InfoMessage += new SqlInfoMessageEventHandler(CnInfoMessage);
cn.FireInfoMessageEventOnUserErrors = true;
SqlCommand cmd = new SqlCommand();
String sql = "dbo.fillTables";
cmd.Connection = cn;
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = sql;
cmd.Parameters.Add(new SqlParameter("#test", 6));
try
{
cn.Open();
SqlDataReader sdr;
sdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
}
catch (SqlException ex)
{
Console.WriteLine(ex.Message);
}
finally
{
cn.Close();
}
}
static void CnInfoMessage(object sender, SqlInfoMessageEventArgs ev)
{
foreach (SqlError err in ev.Errors)
{
Console.WriteLine("Message- " + err.Message);
caller.addMessage(err.Message);
}
}
}
}
form code
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace testDBMessages
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
CGeneral a = new CGeneral(this);
}
private void Form1_Load(object sender, EventArgs e)
{
Application.DoEvents();
}
public void addMessage(string msg)
{
listView1.Items.Add(msg);
listView1.Refresh();
}
}
}
stored procedure
ALTER PROCEDURE [dbo].[fillTables]
(
#test smallint
)
AS
BEGIN
declare #counter as int
SET #counter=1
while #counter<100
BEGIN
Insert into tests.dbo.tToFill (id,description,testNum)
Values (#counter,'test_1',#test)
RAISERROR ('RECORD NUM %d',10,1,#counter)
SET #counter=#counter+1
END
END
GO

Does the user that you connect to your database as using the Integrated security have EXECUTE permission on the stored procedure (dbo.filltables) as that indicates only dbo (database owner) has full permissions on the procedure.
You will need to grant permissions for anyone that wants to use it. Be careful of granting EVERYONE the right if security is a concern.

Your RAISERROR with severity of 10 is classed as a warning so does not flow to client code.
Use 16, which is defined as "Indicates general errors that can be corrected by the user"
(Edit) I'm sure that used to be different...
RAISERROR ('RECORD NUM %d',16,1,#counter)