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);

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

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

Public Function Add (value As SqlParameter) As SqlParameter

Parametri

Valori restituiti

SqlParameter Nuovo oggetto.

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

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

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

public int Add(object value);

public override int Add(object value);

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

override this.Add : obj -> int

Public Function Add (value As Object) As Integer

Public Overrides Function Add (value As Object) As Integer

Parametri

Valori restituiti

Indice del nuovo SqlParameter oggetto.

Implementazioni

Esempio

Nell'esempio seguente viene illustrata l'implementazione dell'interfaccia IList per creare un semplice elenco di dimensioni fisse. 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 del membro dell'interfaccia. Può essere usato solo quando viene eseguito il cast dell'istanza a un'interfaccia SqlParameterCollectionIList .

Vedi anche

• Comandi e parametri (ADO.NET)
• Parametri di 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);

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

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

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

Parametri

Valori restituiti

SqlParameter Nuovo oggetto.

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 di 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

Valori restituiti

SqlParameter Nuovo oggetto.

Prestare attenzione quando si usa questo overload del SqlParameterCollection.Add metodo per specificare i valori di parametro integer. Poiché questo overload accetta un value tipo Object, è necessario convertire il valore integrale in un Object tipo quando il valore è zero, come illustrato nell'esempio C# seguente.

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

Se non si esegue questa conversione, il compilatore presuppone che si stia tentando di chiamare l'overload SqlParameterCollection.Add (string, SqlDbType).

Attributi

ObsoleteAttribute

Eccezioni

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);

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

override 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

Valori restituiti

SqlParameter Nuovo oggetto.

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 di 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);

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

override 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

Valori restituiti

SqlParameter Nuovo oggetto.

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