SqlCeCommand.Parameters Propiedad
Obtiene la colección SqlCeParameterCollection.
Espacio de nombres: System.Data.SqlServerCe
Ensamblado: System.Data.SqlServerCe (en System.Data.SqlServerCe.dll)
Sintaxis
'Declaración
Public ReadOnly Property Parameters As SqlCeParameterCollection
Get
'Uso
Dim instance As SqlCeCommand
Dim value As SqlCeParameterCollection
value = instance.Parameters
public SqlCeParameterCollection Parameters { get; }
public:
property SqlCeParameterCollection^ Parameters {
SqlCeParameterCollection^ get ();
}
member Parameters : SqlCeParameterCollection
function get Parameters () : SqlCeParameterCollection
Valor de la propiedad
Tipo: System.Data.SqlServerCe.SqlCeParameterCollection
Parámetros de la instrucción SQL. El valor predeterminado es una colección vacía.
Comentarios
El proveedor de datos de .NET Compact Framework para SQL Server Compact admite parámetros con nombre para pasar parámetros a una instrucción SQL a la que llama un objeto SqlCeCommand si CommandType se ha establecido en Text. Por ejemplo:
SELECT * FROM Customers WHERE CustomerID = @customerID
Nota
Si los parámetros de la colección no coinciden con los requisitos de la consulta que se va a ejecutar, puede producirse un error.
Ejemplos
En el ejemplo siguiente se crea SqlCeCommand y se establece una matriz de objetos SqlCeParameter.
Dim conn As New SqlCeConnection("Data Source = MyDatabase.sdf;")
conn.Open()
Dim command As SqlCeCommand = conn.CreateCommand()
' Create and prepare a SQL statement
'
command.CommandText = "INSERT INTO Region (RegionID, RegionDescription) VALUES (@id, @desc)"
Dim param As SqlCeParameter = Nothing
' NOTE:
' For optimal performance, make sure you always set the parameter
' type and the maximum size - this is especially important for non-fixed
' types such as NVARCHAR or NTEXT; In case of named parameters,
' SqlCeParameter instances do not need to be added to the collection
' in the order specified in the query; If however you use ? as parameter
' specifiers, then you do need to add the parameters in the correct order
'
param = New SqlCeParameter("@id", SqlDbType.Int)
command.Parameters.Add(param)
param = New SqlCeParameter("@desc", SqlDbType.NVarChar, 100)
command.Parameters.Add(param)
command.Parameters("@desc").Size = 100
' Calling Prepare after having set the CommandText and parameters
'
command.Prepare()
' Execute the SQL statement
'
command.ExecuteNonQuery()
' Change parameter values and call ExecuteNonQuery again
'
command.Parameters(0).Value = 21
command.Parameters(1).Value = "mySecondRegion"
command.ExecuteNonQuery()
SqlCeConnection conn = new SqlCeConnection("Data Source = MyDatabase.sdf;");
conn.Open();
SqlCeCommand command = conn.CreateCommand();
// Create and prepare a SQL statement
//
command.CommandText = "INSERT INTO Region (RegionID, RegionDescription) VALUES (@id, @desc)";
SqlCeParameter param = null;
// NOTE:
// For optimal performance, make sure you always set the parameter
// type and the maximum size - this is especially important for non-fixed
// types such as NVARCHAR or NTEXT; In case of named parameters,
// SqlCeParameter instances do not need to be added to the collection
// in the order specified in the query; If however you use ? as parameter
// specifiers, then you do need to add the parameters in the correct order
//
param = new SqlCeParameter("@id", SqlDbType.Int);
command.Parameters.Add(param);
param = new SqlCeParameter("@desc", SqlDbType.NVarChar, 100);
command.Parameters.Add(param);
command.Parameters["@desc"].Size = 100;
// Calling Prepare after having set the CommandText and parameters
//
command.Prepare();
// Execute the SQL statement
//
command.ExecuteNonQuery();
// Change parameter values and call ExecuteNonQuery again
//
command.Parameters[0].Value = 21;
command.Parameters[1].Value = "mySecondRegion";
command.ExecuteNonQuery();