DbConnectionStringBuilder.ContainsKey(String) Methode

Definition

Namespace:
System.Data.Common
Assembly:
System.Data.Common.dll
Assembly:
System.Data.dll
Assembly:
netstandard.dll

Bestimmt, ob die DbConnectionStringBuilder einen bestimmten Schlüssel enthält.

public:
 virtual bool ContainsKey(System::String ^ keyword);
public virtual bool ContainsKey(string keyword);
abstract member ContainsKey : string -> bool
override this.ContainsKey : string -> bool
Public Overridable Function ContainsKey (keyword As String) As Boolean

Parameter

keyword
String

Der Schlüssel, der in der DbConnectionStringBuilderDatei gefunden werden soll.

Gibt zurück

Boolean

true wenn der DbConnectionStringBuilder Eintrag mit dem angegebenen Schlüssel enthalten ist; andernfalls false.

Ausnahmen

ArgumentNullException

keyword ist ein Nullverweis (Nothing in Visual Basic).

Beispiele

static void Main()
{
    DbConnectionStringBuilder builder = new DbConnectionStringBuilder();
    builder.Add("Provider", "Provider=Microsoft.Jet.OLEDB.4.0");
    builder.Add("Data Source", "C:\\ThisExcelWorkbook.xls");
    builder.Add("Extended Properties", "Excel 8.0;HDR=Yes;IMEX=1");

    // Displays the values in the DbConnectionStringBuilder.
    Console.WriteLine("Contents of the DbConnectionStringBuilder:");
    Console.WriteLine(builder.ConnectionString);

    // Searches for a key.
    if (builder.ContainsKey("Data Source"))
    {
        Console.WriteLine("The collection contains the key \"Data Source\".");
    }
    else
    {
        Console.WriteLine("The collection does not contain the key \"Data Source\".");
    }
    Console.ReadLine();
}

Sub Main()
    ' The following code example searches for an element in a 
    ' DbConnectionStringBuilder.
    Dim builder As New DbConnectionStringBuilder
    builder.Add("Provider", "Provider=Microsoft.Jet.OLEDB.4.0")
    builder.Add("Data Source", "C:\ThisExcelWorkbook.xls")
    builder.Add("Extended Properties", "Excel 8.0;HDR=Yes;IMEX=1")

    ' Displays the values in the DbConnectionStringBuilder.
    Console.WriteLine("Contents of the DbConnectionStringBuilder:")
    Console.WriteLine(builder.ConnectionString)

    ' Searches for a key.
    If builder.ContainsKey("Data Source") Then
        Console.WriteLine("The collection contains the key ""Data Source"".")
    Else
        Console.WriteLine("The collection does not contain the key ""Data Source"".")
    End If
    Console.ReadLine()
End Sub

Mit diesem Code wird die folgende Ausgabe generiert:

Contents of the DbConnectionStringBuilder:
provider="Provider=Microsoft.Jet.OLEDB.4.0";data
source=C:\MyExcel.xls;extended
properties="Excel 8.0;HDR=Yes;IMEX=1"
The collection contains the key "Data Source".

Gilt für:

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