ADO. Net SqlConnection object usage summary

3.1  Generate sqlConnection object

string strConnection ='Data source=.;initial catalog=northwid';

sqlConnection cn = new sqlConnection(strConnection);

3.2 open sqlConnection object

cn.Open();

3.3 close sqlConnection object

cn.Close();

3.4 Self clearing connection

Use using block , Make sure to call Close Method

using (sqlConnection cn = new sqlConnection(strConnection))

{

  cn.Open()

}// When this block is executed , Will implicitly call Close(); Method

3.5.2 Connection string generator

SqlConnectionStringBuilder sb= new SqlConnectionStringBuilder();

sb['Datab Source'][email protected]'./SQLExpress';

sb['Initital Catalog']='Northwind';

sb['Intergrated Security']=true;

// Get string

string strConnection = sb.ConnectionString;

3.7.1 establish sqlCommand

DBCommand cmd = cn.CreateCommand();

cmd.CommandText ='select 1 + 1';

cmd.ExecuteNonQuery();

cmd.CommandText ='Insert into ...';

cmd.ExecuteNonQuery();

3.7.2 Start using sqlTransaction

sqlConnection cn = new sqlConnection(strConnection);

cn.open();

sqlTransaction tn = cn.BeginTransaction();

3.7.3 Get schema information

DataTable tb = cn.GetSchema('Tables');

foreach(DataRow row in tb.rows)

 Console.Write(row['TABLE_NAME']);