Metodo SqlCeResultSet.GetSqlMetaData
Restituisce le informazioni sui metadati associate alla colonna specificata.
Spazio dei nomi System.Data.SqlServerCe
Assembly: System.Data.SqlServerCe (in System.Data.SqlServerCe.dll)
Sintassi
'Dichiarazione
Public Function GetSqlMetaData ( _
ordinal As Integer _
) As SqlMetaData
'Utilizzo
Dim instance As SqlCeResultSet
Dim ordinal As Integer
Dim returnValue As SqlMetaData
returnValue = instance.GetSqlMetaData(ordinal)
public SqlMetaData GetSqlMetaData(
int ordinal
)
public:
SqlMetaData^ GetSqlMetaData(
int ordinal
)
member GetSqlMetaData :
ordinal:int -> SqlMetaData
public function GetSqlMetaData(
ordinal : int
) : SqlMetaData
Parametri
- ordinal
Tipo: System.Int32
Posizione ordinale della colonna da cui recuperare i dati.
Valore restituito
Tipo: System.Data.SqlServerCe.SqlMetaData
Metadati della colonna in corrispondenza dell'indice specificato.
Osservazioni
Se nella posizione ordinale specificata non è presente alcun campo, viene generata un'eccezione.
Esempi
Dim conn As SqlCeConnection = Nothing
Try
File.Delete("Test.sdf")
Dim engine As New SqlCeEngine("Data Source = Test.sdf")
engine.CreateDatabase()
conn = New SqlCeConnection("Data Source = Test.sdf")
conn.Open()
Dim cmd As SqlCeCommand = conn.CreateCommand()
cmd.CommandText = "CREATE TABLE myTable (col1 INT, col2 MONEY, col3 NVARCHAR(200))"
cmd.ExecuteNonQuery()
cmd.CommandText = "SELECT * FROM myTable"
Dim rs As SqlCeResultSet = cmd.ExecuteResultSet(ResultSetOptions.Updatable Or ResultSetOptions.Scrollable)
Dim columnMetaData As SqlMetaData = rs.GetSqlMetaData(2) 'ordinal
MessageBox.Show("Column Name = " & columnMetaData.Name)
MessageBox.Show("Max Length = " & columnMetaData.MaxLength)
MessageBox.Show("Type = " & columnMetaData.SqlDbType)
Catch e As Exception
MessageBox.Show(e.Message)
Finally
conn.Close()
End Try
SqlCeConnection conn = null;
try
{
File.Delete("Test.sdf");
SqlCeEngine engine = new SqlCeEngine("Data Source = Test.sdf");
engine.CreateDatabase();
conn = new SqlCeConnection("Data Source = Test.sdf");
conn.Open();
SqlCeCommand cmd = conn.CreateCommand();
cmd.CommandText = "CREATE TABLE myTable (col1 INT, col2 MONEY, col3 NVARCHAR(200))";
cmd.ExecuteNonQuery();
cmd.CommandText = "SELECT * FROM myTable";
SqlCeResultSet rs = cmd.ExecuteResultSet(ResultSetOptions.Updatable |
ResultSetOptions.Scrollable);
SqlMetaData columnMetaData = rs.GetSqlMetaData(2 /*ordinal*/);
MessageBox.Show("Column Name = " + columnMetaData.Name);
MessageBox.Show("Max Length = " + columnMetaData.MaxLength);
MessageBox.Show("Type = " + columnMetaData.SqlDbType);
}
catch (Exception e)
{
MessageBox.Show(e.Message);
}
finally
{
conn.Close();
}