Csharp/CSharp Tutorial/ADO.Net/SqlException

Catch SqlClient.SqlException

<source lang="csharp">using System; using System.Data; using System.Data.SqlClient; class MainClass {

  static void Main()
  {
        SqlConnection conn = new SqlConnection(@"data source = .\sqlexpress;integrated security = true;database = northwind");
        SqlCommand cmd = conn.CreateCommand();
        cmd.rumandType = CommandType.StoredProcedure;
        cmd.rumandText = "sp_DbException_1";
        try
        {
           conn.Open();
           cmd.ExecuteNonQuery();
        }
        catch (System.Data.SqlClient.SqlException ex)
        {
           Console.WriteLine("Source: " + ex.Source);
           Console.WriteLine("Number: "+ ex.Number.ToString());
           Console.WriteLine("Message: "+ ex.Message);
           Console.WriteLine("Class: "+ ex.Class.ToString ());
           Console.WriteLine("Procedure: "+ ex.Procedure.ToString());
           Console.WriteLine("Line Number: "+ex.LineNumber.ToString());
           Console.WriteLine("Server: "+ ex.Server.ToString());
        }
        catch (System.Exception ex)
        {
           Console.WriteLine("Source: " + ex.Source);
           Console.WriteLine("Exception Message: " + ex.Message);
        }
        finally
        {
           if (conn.State == ConnectionState.Open)
           {
              Console.WriteLine("Finally block closing the connection");
              conn.Close();
           }
        }
  }

}</source>

Catch SqlException when opening connection

<source lang="csharp">using System; using System.Drawing; using System.Collections; using System.ruponentModel; using System.Windows.Forms; using System.Data; using System.Data.OleDb; using System.Data.SqlClient; using System.IO; public class MainClass{

   public static void Main(){
        string ConnectionString ="server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI;";
        SqlConnection conn = new SqlConnection(ConnectionString);
        try
        {
            conn.Open();
        }
        catch(SqlException ae)
        {
            Console.WriteLine("{0}: Threw an Error: ***{1}***"+
                "with SqlServer Code {2}", 
                ae.Errors[0].Server, 
                ae.Errors[0].Message,ae.Errors[0].Number); 
        }
 }

}</source>

Loop through all errors

<source lang="csharp">using System; using System.Data; using System.Data.SqlClient; class MainClass {

  static void Main()
  {
        SqlConnection conn = new SqlConnection(@"data source = .\sqlexpress;integrated security = true;database = northwnd");
        SqlCommand cmd = conn.CreateCommand();
        cmd.rumandType = CommandType.StoredProcedure;
        cmd.rumandText = "error command";
        try
        {
           conn.Open();
           cmd.ExecuteNonQuery();
        }
        catch (System.Data.SqlClient.SqlException ex)
        {
           for (int i = 0; i < ex.Errors.Count; i++)
           {
                Console.WriteLine("Index #" + i);
                Console.WriteLine("Exception: " + ex.Errors[i].ToString() );
                Console.WriteLine("Number: " + ex.Errors[i].Number.ToString() );
           }
        }
        catch (System.Exception ex)
        {
           Console.WriteLine("Source: " + ex.Source);
           Console.WriteLine("Exception Message: " + ex.Message);
        }
        finally
        {
           if (conn.State == ConnectionState.Open)
           {
              Console.WriteLine("Finally block closing the connection");
              conn.Close();
           }
        }
  }

}</source>

Index #0
Exception: System.Data.SqlClient.SqlError: Cannot open database "northwnd" requested by the login. T
he login failed.
Number: 4060
Index #1
Exception: System.Data.SqlClient.SqlError: Login failed for user "nfex\Joe".
Number: 18456