SqlParameterCollection.Add Metodo

public:
 System::Data::SqlClient::SqlParameter ^ Add(System::Data::SqlClient::SqlParameter ^ value);

public System.Data.SqlClient.SqlParameter Add (System.Data.SqlClient.SqlParameter value);

override this.Add : System.Data.SqlClient.SqlParameter -> System.Data.SqlClient.SqlParameter

member this.Add : System.Data.SqlClient.SqlParameter -> System.Data.SqlClient.SqlParameter

Public Function Add (value As SqlParameter) As SqlParameter

Parametri

Restituisce

Nuovo oggetto SqlParameter.

Eccezioni

Esempio

public void AddSqlParameter(SqlCommand command)
{
    command.Parameters.Add(new SqlParameter("Description", "Beverages"));
}

Public Sub AddSqlParameter(command As SqlCommand) 
  command.Parameters.Add(New SqlParameter("Description", "Beverages"))
End Sub

Vedi anche

• Comandi e parametri (ADO.NET)
• Parametri DataAdapter (ADO.NET)
• Uso del provider di dati .NET Framework per SQL Server
• Panoramica di ADO.NET

public:
 override int Add(System::Object ^ value);

public:
 virtual int Add(System::Object ^ value);

public override int Add (object value);

public int Add (object value);

override this.Add : obj -> int

abstract member Add : obj -> int
override this.Add : obj -> int

Public Overrides Function Add (value As Object) As Integer

Public Function Add (value As Object) As Integer

Parametri

Restituisce

Indice del nuovo oggetto SqlParameter.

Implementazioni

Esempio

Nell'esempio riportato di seguito viene illustrata l'implementazione dell'interfaccia IList per creare un elenco semplice di dimensione fissa. Questo codice fa parte di un esempio più ampio per l'interfaccia IList .

class SimpleList : IList
{
    private object[] _contents = new object[8];
    private int _count;

    public SimpleList()
    {
        _count = 0;
    }

    // IList Members
    public int Add(object value)
    {
        if (_count < _contents.Length)
        {
            _contents[_count] = value;
            _count++;

            return (_count - 1);
        }

        return -1;
    }

    public void Clear()
    {
        _count = 0;
    }

    public bool Contains(object value)
    {
        for (int i = 0; i < Count; i++)
        {
            if (_contents[i] == value)
            {
                return true;
            }
        }
        return false;
    }

    public int IndexOf(object value)
    {
        for (int i = 0; i < Count; i++)
        {
            if (_contents[i] == value)
            {
                return i;
            }
        }
        return -1;
    }

    public void Insert(int index, object value)
    {
        if ((_count + 1 <= _contents.Length) && (index < Count) && (index >= 0))
        {
            _count++;

            for (int i = Count - 1; i > index; i--)
            {
                _contents[i] = _contents[i - 1];
            }
            _contents[index] = value;
        }
    }

    public bool IsFixedSize
    {
        get
        {
            return true;
        }
    }

    public bool IsReadOnly
    {
        get
        {
            return false;
        }
    }

    public void Remove(object value)
    {
        RemoveAt(IndexOf(value));
    }

    public void RemoveAt(int index)
    {
        if ((index >= 0) && (index < Count))
        {
            for (int i = index; i < Count - 1; i++)
            {
                _contents[i] = _contents[i + 1];
            }
            _count--;
        }
    }

    public object this[int index]
    {
        get
        {
            return _contents[index];
        }
        set
        {
            _contents[index] = value;
        }
    }

    // ICollection members.

    public void CopyTo(Array array, int index)
    {
        for (int i = 0; i < Count; i++)
        {
            array.SetValue(_contents[i], index++);
        }
    }

    public int Count
    {
        get
        {
            return _count;
        }
    }

    public bool IsSynchronized
    {
        get
        {
            return false;
        }
    }

    // Return the current instance since the underlying store is not
    // publicly available.
    public object SyncRoot
    {
        get
        {
            return this;
        }
    }

    // IEnumerable Members

    public IEnumerator GetEnumerator()
    {
        // Refer to the IEnumerator documentation for an example of
        // implementing an enumerator.
        throw new NotImplementedException("The method or operation is not implemented.");
    }

    public void PrintContents()
    {
        Console.WriteLine($"List has a capacity of {_contents.Length} and currently has {_count} elements.");
        Console.Write("List contents:");
        for (int i = 0; i < Count; i++)
        {
            Console.Write($" {_contents[i]}");
        }
        Console.WriteLine();
    }
}

Public Class SimpleList
    Implements IList

    Private _contents(7) As Object
    Private _count As Integer

    Public Sub New()

        _count = 0
    End Sub

    ' IList members.
    Public Function Add(ByVal value As Object) As Integer Implements IList.Add
        If _count < _contents.Length Then
            _contents(_count) = value
            _count += 1

            Return _count - 1
        End If

        Return -1
    End Function

    Public Sub Clear() Implements IList.Clear
        _count = 0
    End Sub

    Public Function Contains(ByVal value As Object) As Boolean Implements IList.Contains
        For i As Integer = 0 To Count - 1
            If _contents(i) = value Then Return True
        Next

        Return False
    End Function

    Public Function IndexOf(ByVal value As Object) As Integer Implements IList.IndexOf
        For i As Integer = 0 To Count - 1
            If _contents(i) = value Then Return i
        Next
        Return -1
    End Function

    Public Sub Insert(ByVal index As Integer, ByVal value As Object) Implements IList.Insert

        If _count + 1 <= _contents.Length AndAlso index < Count AndAlso index >= 0 Then
            _count += 1

            For i As Integer = Count - 1 To index Step -1
                _contents(i) = _contents(i - 1)
            Next
            _contents(index) = value
        End If
    End Sub

    Public ReadOnly Property IsFixedSize() As Boolean Implements IList.IsFixedSize
        Get
            Return True
        End Get
    End Property

    Public ReadOnly Property IsReadOnly() As Boolean Implements IList.IsReadOnly
        Get
            Return False
        End Get
    End Property

    Public Sub Remove(ByVal value As Object) Implements IList.Remove
        RemoveAt(IndexOf(value))
    End Sub

    Public Sub RemoveAt(ByVal index As Integer) Implements IList.RemoveAt

        if index >= 0 AndAlso index < Count Then
            for i As Integer = index To Count - 2
                _contents(i) = _contents(i + 1)
            Next
            _count -= 1
        End If
    End Sub

    Public Property Item(ByVal index As Integer) As Object Implements IList.Item
        Get
            Return _contents(index)
        End Get

        Set(ByVal value As Object)
            _contents(index) = value
        End Set
    End Property

    ' ICollection members.
    Public Sub CopyTo(ByVal array As Array, ByVal index As Integer) Implements ICollection.CopyTo
        For i As Integer = 0 To Count - 1
            array.SetValue(_contents(i), index)
            index += 1
        Next
    End Sub

    Public ReadOnly Property Count() As Integer Implements ICollection.Count
        Get
            Return _count
        End Get
    End Property

    Public ReadOnly Property IsSynchronized() As Boolean Implements ICollection.IsSynchronized
        Get
            Return False
        End Get
    End Property

    ' Return the current instance since the underlying store is not
    ' publicly available.
    Public ReadOnly Property SyncRoot() As Object Implements ICollection.SyncRoot
        Get
            Return Me
        End Get
    End Property

    ' IEnumerable members.
    Public Function GetEnumerator() As IEnumerator Implements IEnumerable.GetEnumerator

        ' Refer to the IEnumerator documentation for an example of
        ' implementing an enumerator.
        Throw New NotImplementedException("The method or operation is not implemented.")
    End Function

    Public Sub PrintContents()
        Console.WriteLine($"List has a capacity of {_contents.Length} and currently has {_count} elements.")
        Console.Write("List contents:")

        For i As Integer = 0 To Count - 1
            Console.Write($" {_contents(i)}")
        Next

        Console.WriteLine()
    End Sub
End Class

Commenti

Questo membro è un’implementazione esplicita di un membro di interfaccia. Può essere utilizzato solo quando si esegue il cast dell'istanza SqlParameterCollection a un'interfaccia IList.

Vedi anche

• Comandi e parametri (ADO.NET)
• Parametri DataAdapter (ADO.NET)
• Uso del provider di dati .NET Framework per SQL Server
• Panoramica di ADO.NET

public:
 System::Data::SqlClient::SqlParameter ^ Add(System::String ^ parameterName, System::Data::SqlDbType sqlDbType);

public System.Data.SqlClient.SqlParameter Add (string parameterName, System.Data.SqlDbType sqlDbType);

override this.Add : string * System.Data.SqlDbType -> System.Data.SqlClient.SqlParameter

member this.Add : string * System.Data.SqlDbType -> System.Data.SqlClient.SqlParameter

Public Function Add (parameterName As String, sqlDbType As SqlDbType) As SqlParameter

Parametri

Restituisce

Nuovo oggetto SqlParameter.

Esempio

public void AddSqlParameter(SqlCommand command)
{
    SqlParameter param = command.Parameters.Add(
        "@Description", SqlDbType.NVarChar);
    param.Size = 16;
    param.Value = "Beverages";
}

Public Sub AddSqlParameter(command As SqlCommand) 
  Dim param As SqlParameter = command.Parameters.Add( _
      "@Description", SqlDbType.NVarChar)
  param.Size = 16
  param.Value = "Beverages"
End Sub

Vedi anche

• Comandi e parametri (ADO.NET)
• Parametri DataAdapter (ADO.NET)
• Uso del provider di dati .NET Framework per SQL Server
• Panoramica di ADO.NET

public:
 System::Data::SqlClient::SqlParameter ^ Add(System::String ^ parameterName, System::Object ^ value);

public System.Data.SqlClient.SqlParameter Add (string parameterName, object value);

[System.Obsolete("Add(String parameterName, Object value) has been deprecated.  Use AddWithValue(String parameterName, Object value).  http://go.microsoft.com/fwlink/?linkid=14202", false)]
public System.Data.SqlClient.SqlParameter Add (string parameterName, object value);

member this.Add : string * obj -> System.Data.SqlClient.SqlParameter

[<System.Obsolete("Add(String parameterName, Object value) has been deprecated.  Use AddWithValue(String parameterName, Object value).  http://go.microsoft.com/fwlink/?linkid=14202", false)>]
override this.Add : string * obj -> System.Data.SqlClient.SqlParameter

Public Function Add (parameterName As String, value As Object) As SqlParameter

Parametri

Restituisce

Nuovo oggetto SqlParameter.

Prestare attenzione quando si utilizza l'overload del metodo SqlParameterCollection.Add per specificare valori di parametro di tipo Integer. Poiché l'overload accetta un value di tipo Object, è necessario convertire il valore integrale in un tipo Object, come illustrato nell'esempio C# riportato di seguito.

parameters.Add("@pname", Convert.ToInt32(0));

Se non si esegue questa conversione, il compilatore si comporterà come se si tentasse di chiamare l'overload SqlParameterCollection.Add (string, SqlDbType).

Attributi

ObsoleteAttribute

Eccezioni

Esempio

public void AddSqlParameter(SqlCommand command)
{
    SqlParameter param = new SqlParameter(
        "@Description", SqlDbType.NVarChar, 16);
    param.Value = "Beverages";
    command.Parameters.Add(param);
}

Public Sub AddSqlParameter(command As SqlCommand) 
  Dim param As New SqlParameter( _
      "@Description", SqlDbType.NVarChar, 16)
  param.Value = "Beverages"
  command.Parameters.Add(param)
End Sub

Vedi anche

• Panoramica di ADO.NET

public:
 System::Data::SqlClient::SqlParameter ^ Add(System::String ^ parameterName, System::Data::SqlDbType sqlDbType, int size);

public System.Data.SqlClient.SqlParameter Add (string parameterName, System.Data.SqlDbType sqlDbType, int size);

override this.Add : string * System.Data.SqlDbType * int -> System.Data.SqlClient.SqlParameter

member this.Add : string * System.Data.SqlDbType * int -> System.Data.SqlClient.SqlParameter

Public Function Add (parameterName As String, sqlDbType As SqlDbType, size As Integer) As SqlParameter

Parametri

Restituisce

Nuovo oggetto SqlParameter.

Esempio

public void AddSqlParameter(SqlCommand command)
{
    SqlParameter param = new SqlParameter(
        "@Description", SqlDbType.NVarChar, 16);
    param.Value = "Beverages";
    command.Parameters.Add(param);
}

Public Sub AddSqlParameter(command As SqlCommand) 
  Dim param As New SqlParameter( _
      "@Description", SqlDbType.NVarChar, 16)
  param.Value = "Beverages"
  command.Parameters.Add(param)
End Sub

Commenti

Questo overload è utile quando si aggiunge un parametro di un tipo di dati a lunghezza variabile, varchar ad esempio o binary.

Vedi anche

• Comandi e parametri (ADO.NET)
• Parametri DataAdapter (ADO.NET)
• Uso del provider di dati .NET Framework per SQL Server
• Panoramica di ADO.NET

public:
 System::Data::SqlClient::SqlParameter ^ Add(System::String ^ parameterName, System::Data::SqlDbType sqlDbType, int size, System::String ^ sourceColumn);

public System.Data.SqlClient.SqlParameter Add (string parameterName, System.Data.SqlDbType sqlDbType, int size, string sourceColumn);

override this.Add : string * System.Data.SqlDbType * int * string -> System.Data.SqlClient.SqlParameter

member this.Add : string * System.Data.SqlDbType * int * string -> System.Data.SqlClient.SqlParameter

Public Function Add (parameterName As String, sqlDbType As SqlDbType, size As Integer, sourceColumn As String) As SqlParameter

Parametri

Restituisce

Nuovo oggetto SqlParameter.

Esempio

public void AddSqlParameter(SqlCommand cmd)
{
  SqlParameter p1 = cmd.Parameters.Add("@Description", SqlDbType.NVarChar, 16, "Description");
}

Public Sub AddSqlParameter(cmd As SqlCommand) 
  Dim p1 As SqlParameter = cmd.Parameters.Add("@Description", SqlDbType.NVarChar, 16, "Description")
End Sub

Vedi anche

• Comandi e parametri (ADO.NET)
• Parametri DataAdapter (ADO.NET)
• Uso del provider di dati .NET Framework per SQL Server
• Panoramica di ADO.NET