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How to Insert C# values to MySql?

I want to insert C# winform values to Mysql
there are 3 columns
name,id are TextBox text and gender is ComboBox value
but there is error and error messsage said: MySql.Data.MySqlClient.MySqlException: 'You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '',')' at line 1'
what code should i fix?
using (MySqlConnection conn2 = new MySqlConnection(strconn))
{
conn2.Open();
string query = "INSERT INTO student1(name,id,gender) values ('" + name3.Text + "'," + id3.Text + "'," + gender3.SelectedValue+"');";
MySqlCommand cmd = new MySqlCommand(query, conn2);
cmd.ExecuteNonQuery();
}

You're missing a single quote in the connecting string literal between name3.Text and id3.Text and again between id3.Text and gender3.SelectedValue
But it shouldn't matter. If you're concatenating user-supplied strings like this it's only a matter of time until your system is breached. There's a better way that avoids this risk, makes it easier to get your SQL statements correct, and runs faster.
//This could be marked const!
string query = "INSERT INTO student1(name,id,gender) values (#name, #id, #gender);";
using (var conn2 = new MySqlConnection(strconn))
using (var cmd = new MySqlCommand(query, conn2))
{
//I have to guess, but you can find exact column types/lengths from your db
//Do not use AddWithValue()!
// MySql is less at risk for the AddWithValue() performance issues
// than Sql Server but the risk isn't completely eliminated.
cmd.Parameters.Add("#name", MySqlDbType.VarChar, 30).Value = name3.Text;
cmd.Parameters.Add("#id", MySqlDbType.VarChar, 50).Value = id3.Text;
cmd.Parameters.Add("#gender", MySqlDbType.VarChar, 5).Value = gender3.SelectedValue;
conn2.Open();
cmd.ExecuteNonQuery();
}

using (MySqlConnection conn2 = new MySqlConnection(strconn))
{
String query = "INSERT INTO student1(name,id,gender) values (#name,#id,#gender)";
MySqlCommand = new MySqlCommand(query, conn2);
command.Parameters.AddWithValue("#name", name3.Text);
command.Parameters.AddWithValue("#id", id3.Text);
command.Parameters.AddWithValue("#gender", gender3.SelectedValue.ToString());
command.ExecuteNonQuery();
}
use need use parameters

Adding rows to a SQL Server database from data entered by user in asp.net c#

string ConnectionString = WebConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
SqlConnection connection = new SqlConnection(ConnectionString);
SqlCommand cmd = new SqlCommand("INSERT INTO Data (Name, Sur-Name, Score,Avg) VALUES ('" + fName + "','" + sName + "','" + lblScore.Text + "','" + lblAvg.Text + "');");
cmd.CommandType = CommandType.Text;
cmd.Connection = connection;
cmd.Parameters.AddWithValue("#Name", fName);
cmd.Parameters.AddWithValue("#Sur-Name", sName);
cmd.Parameters.AddWithValue("#Score", lblScore.Text);
cmd.Parameters.AddWithValue("#Avg", lblAvg.Text);
try
{
connection.Open();
cmd.ExecuteNonQuery();
}
catch (Exception exc)
{
lblData.Text = exc.Message;
}
finally
{
connection.Close();
}
The error I keep getting is a runtime saying
Incorrect syntax near '-'. Incorrect syntax near '-'.
I used the try catch just so page would load and my scores show but the label says this Incorrect syntax as well, I was wondering could anyone please help me with what I am doing wrong
Thanks.

I think Sur-Name breaks your query. Use it with square brackets like [Sur-Name]
But more important, please use parameterized queries. This kind of string concatenations are open for SQL Injection attacks. I see you tried to use but you never declare your parameter names in your query.
Also DATA might be a reserved keyword on future versions of SQL Server. You might need to use with also like [DATA]
Consider to use using statement to dispose your SqlConnection and SqlCommand.
using(SqlConnection connection = new SqlConnection(ConnectionString))
using(SqlCommand cmd = connection.CreateCommand())
{
cmd.CommandText = #"INSERT INTO [Data] (Name, [Sur-Name], Score, Avg)
VALUES (#Name, #SurName, #Score, #Avg)";
cmd.Connection = connection;
cmd.Parameters.AddWithValue("#Name", fName);
cmd.Parameters.AddWithValue("#SurName", sName);
cmd.Parameters.AddWithValue("#Score", lblScore.Text);
cmd.Parameters.AddWithValue("#Avg", lblAvg.Text);
try
{
connection.Open();
cmd.ExecuteNonQuery();
}
catch (Exception exc)
{
lblData.Text = exc.Message;
}
}

You are trying to mix concatenated queries with parametrized. Always use parametrized queries, It will save you from SQL Injection.
SqlCommand cmd = new SqlCommand(#"INSERT INTO [Data] (Name, [Sur-Name], Score,Avg) VALUES (
#Name, #SurName, #Score, #Avg)");
cmd.CommandType = CommandType.Text;
cmd.Connection = connection;
cmd.Parameters.AddWithValue("#Name", fName);
cmd.Parameters.AddWithValue("#SurName", sName);
cmd.Parameters.AddWithValue("#Score", lblScore.Text);
cmd.Parameters.AddWithValue("#Avg", lblAvg.Text);
Also consider enclosing your connection and command object in using statement.
As #Soner has mentioned in his answer, use Square brackets for Data and Sur-Name

C# MySql.Data INSERT INTO error

I use the MySql.Data in c# for a mysql connection. On another program it worked but currently i'm hanging on the INSERT INTO command.
I get the following error:
An unhandled exception of type 'MySql.Data.MySqlClient.MySqlException' occurred in MySql.Data.dll
Additional information: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'key) VALUES ('PGJWZBPOWTRPUTKY')' at line 1
With this code:
MySqlCommand Command = Connection.CreateCommand();
MySqlDataReader Reader;
Command.CommandText = "INSERT INTO jt_teamsync (key) VALUES ('" + TeamSyncKey + "')";
Connection.Open();
Reader = Command.ExecuteReader();
Connection.Close();
Thanks for any help

KEY is a reserved keyword in mysql. It should be escaped using backtick,
INSERT INTO jt_teamsync (`key`) VALUES(...)
MySQL Reserved Keywords List
As a sidenote, your query is very weak. It is vulnerable with SQL Injection. Parameterized the value to avoid from it, eg
string content = TeamSyncKey;
string connStr = "connection string here";
string sqlStatement = "INSERT INTO jt_teamsync (`key`) VALUES (#key)";
using (MySqlConnection conn = new MySqlConnection(connStr))
{
using(MySqlCommand comm = new MySqlCommand())
{
comm.Connection = conn;
comm.CommandText = sqlStatement;
comm.CommandType = CommandType.Text;
comm.Parameters.AddWithValue("#key", content);
try
{
conn.Open();
comm.ExecuteNonQuery();
}
catch(MySqlException e)
{
// do something with the exception
// do not hide it
// e.Message.ToString()
}
}
}

How to run multiple SQL commands in a single SQL connection?

I am creating a project in which I need to run 2-3 SQL commands in a single SQL connection.
Here is the code I have written:
SqlConnection con = new SqlConnection(#"Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\project.mdf;Integrated Security=True");
con.Open();
SqlCommand cmd = new SqlCommand("select * from " + mytags.Text + " ", con);
SqlDataReader rd = cmd.ExecuteReader();
if (rd.Read())
{
con.Close();
con.Open();
SqlCommand cmd1 = new SqlCommand("insert into " + mytags.Text + " values ('fname.lname#gmail.com','" + TextBox3.Text + "','" + TextBox4.Text + "','" + TextBox5.Text + "','"+mytags.Text+"')", con);
cmd1.ExecuteNonQuery();
label.Visible = true;
label.Text = "Date read and inserted";
}
else
{
con.Close();
con.Open();
SqlCommand cmd2 = new SqlCommand("create table " + mytags.Text + " ( session VARCHAR(MAX) , Price int , Description VARCHAR(MAX), Date VARCHAR(20),tag VARCHAR(10))", con);
cmd2.ExecuteNonQuery();
con.Close();
con.Open();
SqlCommand cmd3 = new SqlCommand("insert into " + mytags.Text + " values ('" + Session + "','" + TextBox3.Text + "','" + TextBox4.Text + "','" + TextBox5.Text + "','" + mytags.Text + "')", con);
cmd3.ExecuteNonQuery();
label.Visible = true;
label.Text = "tabel created";
con.Close();
}
I have tried to remove the error and I got that the connection is not going to else condition. Please review the code and suggest if there is any mistake or any other solution for this.

Just change the SqlCommand.CommandText instead of creating a new SqlCommand every time. There is no need to close and reopen the connection.
// Create the first command and execute
var command = new SqlCommand("<SQL Command>", myConnection);
var reader = command.ExecuteReader();
// Change the SQL Command and execute
command.CommandText = "<New SQL Command>";
command.ExecuteNonQuery();

The following should work. Keep single connection open all time, and just create new commands and execute them.
using (SqlConnection connection = new SqlConnection(connectionString))
{
connection.Open();
using (SqlCommand command1 = new SqlCommand(commandText1, connection))
{
}
using (SqlCommand command2 = new SqlCommand(commandText2, connection))
{
}
// etc
}

Just enable this property in your connection string:
sqb.MultipleActiveResultSets = true;
This property allows one open connection for multiple datareaders.

I have not tested , but what the main idea is: put semicolon on each query.
SqlConnection connection = new SqlConnection();
SqlCommand command = new SqlCommand();
connection.ConnectionString = connectionString; // put your connection string
command.CommandText = #"
update table
set somecol = somevalue;
insert into someTable values(1,'test');";
command.CommandType = CommandType.Text;
command.Connection = connection;
try
{
connection.Open();
}
finally
{
command.Dispose();
connection.Dispose();
}
Update:
you can follow
Is it possible to have multiple SQL instructions in a ADO.NET Command.CommandText property? too

This is likely to be attacked via SQL injection by the way. It'd be worth while reading up on that and adjusting your queries accordingly.
Maybe look at even creating a stored proc for this and using something like sp_executesql which can provide some protection against this when dynamic sql is a requirement (ie. unknown table names etc). For more info, check out this link.

No one has mentioned this, but you can also separate your commands using a ; semicolon in the same CommandText:
using (SqlConnection conn = new SqlConnection(connString))
{
using (SqlCommand comm = new SqlCommand())
{
comm.Connection = conn;
comm.CommandText = #"update table ... where myparam=#myparam1 ; " +
"update table ... where myparam=#myparam2 ";
comm.Parameters.AddWithValue("#myparam1", myparam1);
comm.Parameters.AddWithValue("#myparam2", myparam2);
conn.Open();
comm.ExecuteNonQuery();
}
}

Multiple Non-query example if anyone is interested.
using (OdbcConnection DbConnection = new OdbcConnection("ConnectionString"))
{
DbConnection.Open();
using (OdbcCommand DbCommand = DbConnection.CreateCommand())
{
DbCommand.CommandText = "INSERT...";
DbCommand.Parameters.Add("#Name", OdbcType.Text, 20).Value = "name";
DbCommand.ExecuteNonQuery();
DbCommand.Parameters.Clear();
DbCommand.Parameters.Add("#Name", OdbcType.Text, 20).Value = "name2";
DbCommand.ExecuteNonQuery();
}
}

Here you can find Postgre example, this code run multiple sql commands (update 2 columns) within single SQL connection
public static class SQLTest
{
public static void NpgsqlCommand()
{
using (NpgsqlConnection connection = new NpgsqlConnection("Server = ; Port = ; User Id = ; " + "Password = ; Database = ;"))
{
NpgsqlCommand command1 = new NpgsqlCommand("update xy set xw = 'a' WHERE aa='bb'", connection);
NpgsqlCommand command2 = new NpgsqlCommand("update xy set xw = 'b' where bb = 'cc'", connection);
command1.Connection.Open();
command1.ExecuteNonQuery();
command2.ExecuteNonQuery();
command2.Connection.Close();
}
}
}

using (var connection = new SqlConnection("Enter Your Connection String"))
{
connection.Open();
using (var command = connection.CreateCommand())
{
command.CommandText = "Enter the First Command Here";
command.ExecuteNonQuery();
command.CommandText = "Enter Second Comand Here";
command.ExecuteNonQuery();
//Similarly You can Add Multiple
}
}
It worked for me.

Using parameters inserting data into access database

I have the following method to inserting data into an an access databasewhich works fine but I do get a problem if I try to insert text that contains single quotes I have learned.
[WebMethod]
public void bookRatedAdd(string title, int rating, string review, string ISBN, string userName)
{
OleDbConnection conn;
conn = new OleDbConnection(#"Provider=Microsoft.Jet.OleDb.4.0;
Data Source=" + Server.MapPath("App_Data\\BookRateInitial.mdb"));
conn.Open();
OleDbCommand cmd = conn.CreateCommand();
cmd.CommandText = #"INSERT INTO bookRated([title], [rating], [review], [frnISBN], [frnUserName])VALUES('" + title + "', '" + rating + "','" + review + "','" + ISBN + "', '" + userName + "')";
cmd.ExecuteNonQuery();
conn.Close();
}
From what I understand one of the ways to solve the problem is by using parameters. I am not sure how to do this to be honest. How could I change the above code so that I insert the data by using parameters instead?

Same as for any other query:
a) Replace actual hardcoded parameters in your OleDbCommand with placeholders (prefixed with #),
b) Add instances of OleDbParameter to the DbCommand.Parameters property. Parameter names must match placeholder names.
[WebMethod]
public void bookRatedAdd(string title, int rating, string review, string ISBN, string userName)
{
using (OleDbConnection conn = new OleDbConnection(
"Provider=Microsoft.Jet.OleDb.4.0;"+
"Data Source="+Server.MapPath("App_Data\\BookRateInitial.mdb"));
{
conn.Open();
// DbCommand also implements IDisposable
using (OleDbCommand cmd = conn.CreateCommand())
{
// create command with placeholders
cmd.CommandText =
"INSERT INTO bookRated "+
"([title], [rating], [review], [frnISBN], [frnUserName]) "+
"VALUES(#title, #rating, #review, #isbn, #username)";
// add named parameters
cmd.Parameters.AddRange(new OleDbParameter[]
{
new OleDbParameter("#title", title),
new OleDbParameter("#rating", rating),
...
});
// execute
cmd.ExecuteNonQuery();
}
}
}

You have to use Parameter to insert Values. Its is allso a security Issue.
If you do it like that a sql injection could by made.
Try like this:
string ConnString = Utils.GetConnString();
string SqlString = "Insert Into Contacts (FirstName, LastName) Values (?,?)";
using (OleDbConnection conn = new OleDbConnection(ConnString))
{
using (OleDbCommand cmd = new OleDbCommand(SqlString, conn))
{
cmd.CommandType = CommandType.Text;
cmd.Parameters.AddWithValue("FirstName", txtFirstName.Text);
cmd.Parameters.AddWithValue("LastName", txtLastName.Text);
conn.Open();
cmd.ExecuteNonQuery();
}
}

For Microsoft Access the parameters are positional based and not named, you should use ? as the placeholder symbol although the code would work if you used name parameters provided they are in the same order.
See the documentation for OleDbCommand.Parameters Property
Remarks
The OLE DB .NET Provider does not support named parameters for passing parameters to an SQL statement or a stored procedure called by an OleDbCommand when CommandType is set to Text. In this case, the question mark (?) placeholder must be used. For example:
SELECT * FROM Customers WHERE CustomerID = ?
Therefore, the order in which OleDbParameter objects are added to the OleDbParameterCollection must directly correspond to the position of the question mark placeholder for the parameter in the command text.
Be sure to include the expected schema type where the parameter will be used AND the schema length if applicable.
I also recommend you always use using statements around your instances where the type implements IDisposable like the OleDbConnection so that the connection is always closed even if an exception is thrown in the code.
Changed Code:
var connectionStringHere = #"Provider=Microsoft.Jet.OleDb.4.0;Data Source=" + Server.MapPath("App_Data\\BookRateInitial.mdb";
using (var conn = new OleDbConnection(connectionStringHere))
using (var cmd = conn.CreateCommand())
{
cmd.CommandText = "INSERT INTO bookRated ([title], [rating], [review], [frnISBN], [frnUserName]) VALUES(?, ?, ?, ?, ?)";
cmd.Parameters.Add(new OleDbParameter("?", OleDbType.VarChar, 100) { Value = title});
cmd.Parameters.Add(new OleDbParameter("?", OleDbType.Integer) { Value = rating });
cmd.Parameters.Add(new OleDbParameter("?", OleDbType.VarChar, 2000) { Value = review });
cmd.Parameters.Add(new OleDbParameter("?", OleDbType.VarChar, 60) { Value = ISBN });
cmd.Parameters.Add(new OleDbParameter("?", OleDbType.VarChar, 256) { Value = userName });
conn.Open();
var numberOfRowsInserted = cmd.ExecuteNonQuery();
}