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OdbcConnectionStringBuilder.ContainsKey(String) Method

Definition

Determines whether the OdbcConnectionStringBuilder contains a specific key.

C#
public override bool ContainsKey(string keyword);

Parameters

keyword
String

The key to locate in the OdbcConnectionStringBuilder.

Returns

true if the OdbcConnectionStringBuilder contains an element that has the specified key; otherwise false.

Exceptions

keyword is null (Nothing in Visual Basic).

Examples

The following example creates an OdbcConnectionStringBuilder instance, sets some of its properties, and then tries to determine whether various keys exist within the object by calling the ContainsKey method.

C#
using System.Data.Odbc;

class Program
{
    static void Main()
    {
        OdbcConnectionStringBuilder  builder = new OdbcConnectionStringBuilder();
        builder.Driver = "Microsoft Visual FoxPro Driver";
        builder["SourceType"] = "DBC";

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

        // Comparison is case insensitive.
        Console.WriteLine(builder.ContainsKey("sourcetype"));

        // Keys added by the provider return false. This method
        // only examines keys added explicitly.
        Console.WriteLine(builder.ContainsKey("DNS"));

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

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

Applies to

Продукт Версии
.NET 8 (package-provided), 9 (package-provided), 10 (package-provided)
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0 (package-provided)

See also