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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: 4.6, 4.5, 4, 3.5, 3.0, 2.0
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