SqlConnectionStringBuilder.ContainsKey(String) Méthode

  • Référence

Définition

Espace de noms:
System.Data.SqlClient
Assembly:
System.Data.SqlClient.dll
Assembly:
System.Data.dll
Paquet:
System.Data.SqlClient v4.8.6

Détermine si SqlConnectionStringBuilder contient une clé spécifique.

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

Paramètres

keyword
String

Clé à rechercher dans SqlConnectionStringBuilder.

Retours

Boolean

true si SqlConnectionStringBuilder contient un élément qui possède la clé spécifiée ; sinon, false.

Exceptions

ArgumentNullException

keyword a la valeur Null (Nothing en Visual Basic).

Exemples

L’exemple suivant crée un SqlConnectionStringBuilder instance, définit certaines de ses propriétés, puis tente de déterminer si différentes clés existent dans l’objet en appelant la méthode ContainsKey.

using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        SqlConnectionStringBuilder builder =
            new SqlConnectionStringBuilder(GetConnectionString());
        Console.WriteLine("Connection string = " + builder.ConnectionString);

        // Keys you have provided return true.
        Console.WriteLine(builder.ContainsKey("Server"));

        // Comparison is case insensitive, and synonyms
        // are automatically converted to their "well-known"
        // names.
        Console.WriteLine(builder.ContainsKey("Database"));

        // Keys that are valid but have not been set return true.
        Console.WriteLine(builder.ContainsKey("Max Pool Size"));

        // Keys that do not exist return false.
        Console.WriteLine(builder.ContainsKey("MyKey"));

        Console.WriteLine("Press Enter to continue.");
        Console.ReadLine();
    }

    private static string GetConnectionString()
    {
        // To avoid storing the connection string in your code,
        // you can retrieve it from a configuration file.
        return "Server=(local);Integrated Security=SSPI;" +
            "Initial Catalog=AdventureWorks";
    }
}

Imports System.Data.SqlClient

Module Module1
    Sub Main()
        Dim builder As _
         New SqlConnectionStringBuilder(GetConnectionString())
        Console.WriteLine("Connection string = " & builder.ConnectionString)

        ' Keys you have provided return true.
        Console.WriteLine(builder.ContainsKey("Server"))

        ' Comparison is case insensitive, and synonyms
        ' are automatically converted to their "well-known"
        ' names.
        Console.WriteLine(builder.ContainsKey("Database"))

        ' Keys that are valid but have not been set return true.
        Console.WriteLine(builder.ContainsKey("Max Pool Size"))

        ' Keys that do not exist return false.
        Console.WriteLine(builder.ContainsKey("MyKey"))

        Console.WriteLine("Press Enter to continue.")
        Console.ReadLine()
    End Sub

    Private Function GetConnectionString() As String
        ' To avoid storing the connection string in your code,
        ' you can retrieve it from a configuration file. 
        Return "Server=(local);Integrated Security=SSPI;" & _
          "Initial Catalog=AdventureWorks"
    End Function
End Module

L'exemple affiche la sortie suivante dans la fenêtre de console :

Connection string = Data Source=(local);Initial Catalog=AdventureWorks;Integrated Security=True
True
True
True
False

Remarques

Étant donnée que SqlConnectionStringBuilder contient une collection de taille fixe de paires clé/valeur, la méthode ContainsKey détermine uniquement si le nom d'une clé particulière est valide.

S’applique à

Voir aussi