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OracleConnectionStringBuilder.TryGetValue Method

Retrieves a value corresponding to the supplied key from this OracleConnectionStringBuilder.

Namespace:  System.Data.OracleClient
Assembly:  System.Data.OracleClient (in System.Data.OracleClient.dll)

public override bool TryGetValue(
	string keyword,
	out Object value
)

Parameters

keyword
Type: System.String

The key of the item to retrieve.

value
Type: System.Object

The value corresponding to keyword.

Return Value

Type: System.Boolean
true if keyword was found within the connection string; otherwise, false.

The TryGetValue method lets developers safely retrieve a value from an OracleConnectionStringBuilder without needing to verify that the supplied key name is a valid key name. Because TryGetValue gracefully handles searching for a non-existent key, there is no need to look for the existence of a key before retrieving its value. Calling TryGetValue with a nonexistent key will place the value null (Nothing in Visual Basic) in the value parameter.

The following example demonstrates the behavior of the TryGetValue method.

// 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();
        builder.ConnectionString = GetConnectionString();

        // Call TryGetValue method for multiple 
        // key names. Note that these keys are converted 
        // to well-known synonynms for data retrieval.
        DisplayValue(builder, "Data Source");
        DisplayValue(builder, "Trusted_Connection");
        DisplayValue(builder, "InvalidKey");
        DisplayValue(builder, null);

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

    private static void DisplayValue(OracleConnectionStringBuilder builder, string key)
    {
        object value = null;

        // Although TryGetValue handles missing keys, 
        // it does not handle passing in a null 
        // key. This example traps for that particular error, but 
        // passes any other unknown exceptions back out to the 
        // caller.  
        try
        {
            if (builder.TryGetValue(key, out value))
            {
                Console.WriteLine("{0}='{1}'", key, value);
            }
            else
            {
                Console.WriteLine("Unable to retrieve value for '{0}'", key);
            }
        }
        catch (ArgumentNullException)
        {
            Console.WriteLine("Unable to retrieve value for null key.");
        }
    }

    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";
    }
}

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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