C# – How to run multiple SQL commands in a single SQL connection

ado.netcsql serversqlcommandsqlconnection

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.

Best Answer

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();
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