OracleConnectionStringBuilder.ContainsKey(String) 方法

定义

确定 OracleConnectionStringBuilder 是否包含特定键。

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

参数

keyword
String

要在 OracleConnectionStringBuilder 中定位的键。

返回

如果 OracleConnectionStringBuilder 包含具有指定键的元素,则为 true;否则为 false

例外

keyword 为 Null(在 Visual Basic 中为 Nothing

示例

以下示例创建一个 OracleConnectionStringBuilder 实例,设置其一些属性,然后尝试通过调用 ContainsKey 方法来确定对象中是否存在各种键。

// You may need to set a reference to the System.Data.OracleClient
// assembly before you can run this sample.
using System.Data.OracleClient;

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

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

        // Comparison is case insensitive, and synonyms for the
        // keywords are translated to well-known names.
        // The following returns true because "PWD" is a
        // synonym for "Password", a valid key.
        Console.WriteLine(builder.ContainsKey("PWD"));

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

        // 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=OracleDemo;Integrated Security=True";
    }
}
' You may need to set a reference to the System.Data.OracleClient
' assembly before you can run this sample.
Imports System.Data.OracleClient

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

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

    ' Comparison is case insensitive, and synonyms for the 
    ' keywords are translated to well-known names.
    ' The following returns True because "PWD" is a 
    ' synonym for "Password", a valid key.
    Console.WriteLine(builder.ContainsKey("PWD"))

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

    ' Keys that don't 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=OracleDemo;Integrated Security=True"
  End Function
End Module

注解

由于 OracleConnectionStringBuilder 包含固定大小的键/值对集合,因此 ContainsKey 方法只确定特定键名是否有效。

适用于

另请参阅