SqlParameterCollection.Contains Methode

  • Referenz

Definition

Namespace:
System.Data.SqlClient
Assembly:
System.Data.SqlClient.dll
Assembly:
System.Data.dll
Paket:
System.Data.SqlClient v4.9.0

Bestimmt, ob das angegebene Objekt in dieser SqlParameterCollection vorhanden ist.

Überlädt

Contains(SqlParameter)

Bestimmt, ob der angegebene SqlParameter in dieser SqlParameterCollection vorhanden ist.
Contains(Object)

Bestimmt, ob der angegebene Object in dieser SqlParameterCollection vorhanden ist.
Contains(String)

Bestimmt, ob der angegebene Parametername in diesem SqlParameterCollection ist.

Contains(SqlParameter)

Quelle:
System.Data.SqlClient.notsupported.cs

Bestimmt, ob der angegebene SqlParameter in dieser SqlParameterCollection vorhanden ist.

public:
 bool Contains(System::Data::SqlClient::SqlParameter ^ value);
public bool Contains (System.Data.SqlClient.SqlParameter value);
override this.Contains : System.Data.SqlClient.SqlParameter -> bool
Public Function Contains (value As SqlParameter) As Boolean

Parameter

value
SqlParameter

Der SqlParameter-Wert.

Gibt zurück

Boolean

true, wenn das SqlParameterCollection-Objekt den Wert enthält, andernfalls false.

Weitere Informationen

Gilt für:

Contains(Object)

Quelle:
System.Data.SqlClient.notsupported.cs

Bestimmt, ob der angegebene Object in dieser SqlParameterCollection vorhanden ist.

public:
 override bool Contains(System::Object ^ value);
public:
 virtual bool Contains(System::Object ^ value);
public override bool Contains (object value);
public bool Contains (object value);
override this.Contains : obj -> bool
abstract member Contains : obj -> bool
override this.Contains : obj -> bool
Public Overrides Function Contains (value As Object) As Boolean
Public Function Contains (value As Object) As Boolean

Parameter

value
Object

Der Object-Wert.

Gibt zurück

Boolean

true, wenn das SqlParameterCollection-Objekt den Wert enthält, andernfalls false.

Implementiert

Contains(Object)

Beispiele

Im folgenden Beispiel wird die Implementierung der IList Schnittstelle veranschaulicht, um eine einfache Liste mit fester Größe zu erstellen. Dieser Code ist Teil eines größeren Beispiels für die IList Schnittstelle.

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

Hinweise

Bei diesem Member handelt es sich um eine explizite Schnittstellenmemberimplementierung. Er kann nur verwendet werden, wenn die SqlParameterCollection-Instanz in eine IList-Schnittstelle umgewandelt wird.

Ab dem .NET Framework 2.0 verwendet diese Methode die -Objekte Equals und CompareTo -Methoden item der Auflistung, um zu bestimmen, ob ein Element vorhanden ist. In den früheren Versionen des .NET Framework wurde diese Bestimmung mithilfe der Equals Methoden und CompareTo des item Parameters für die -Objekte in der Auflistung vorgenommen.

Weitere Informationen

Gilt für:

Contains(String)

Quelle:
System.Data.SqlClient.notsupported.cs

Bestimmt, ob der angegebene Parametername in diesem SqlParameterCollection ist.

public:
 override bool Contains(System::String ^ value);
public:
 virtual bool Contains(System::String ^ value);
public override bool Contains (string value);
public bool Contains (string value);
override this.Contains : string -> bool
abstract member Contains : string -> bool
override this.Contains : string -> bool
Public Overrides Function Contains (value As String) As Boolean
Public Function Contains (value As String) As Boolean

Parameter

value
String

Der String-Wert.

Gibt zurück

Boolean

true, wenn das SqlParameterCollection-Objekt den Wert enthält, andernfalls false.

Implementiert

Contains(String)

Weitere Informationen

Gilt für: