Question

I have a problem with inserting a TextBox value into a SqlServer table. I wrote that code, but when I run the form it raises a runtime error: “a network-related or instance-specific error occurred while establishing a connection to sql server”. Thanks in advance.

public partial class Add_Client : Form
{
    SqlConnection clientConnection;
    string connString;
    SqlCommand insertCommand; 

    public Add_Client()
    {
        InitializeComponent();
        connString = "Data Source=.//INSTANCE2;Initial Catalog=Clients;Integrated Security=True";
        clientConnection = new SqlConnection();
        clientConnection.ConnectionString = connString;
    }

    private void button1_Click(object sender, EventArgs e)
    {
        try
        {
            SqlCommand insertCommand = new SqlCommand();
            insertCommand.Connection = clientConnection;
            insertCommand.CommandText = "INSERT INTO Client_Info values(@Client_Name,@AutorizationNo,@IssueType,@Status)";
            insertCommand.Parameters.Add("@Client_Name",SqlDbType.NVarChar,60).Value=txt_Name.Text;
            insertCommand.Parameters.Add("@AutorizationNo", SqlDbType.Int, 60).Value =txt_Auth.Text.ToString();
            insertCommand.Parameters.Add("@Issue", SqlDbType.Text, 200).Value =txt_Iss.Text;
            insertCommand.Parameters.Add("@Status", SqlDbType.TexT, 15).Value=txt_sta.TexT;
            insertCommand.Connection.Open();
            insertCommand.ExecuteNonQuery();
        }
        catch (Exception ex)
        {
            throw ex;
        }
        finally
        {
            if (clientConnection != null)
            {
                clientConnection.Close();
            }
        }
    }
}

Answer 1

the .// in the host name in your connection string shouldn’t be there. i wouldn’t expect it to work. you should just have the machine name itself there.