DbConnectionStringBuilder.TryGetValue Method (String, Object)


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

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

public virtual bool TryGetValue(
	string keyword,
	out object value


Type: System.String

The key of the item to retrieve.

Type: System.Object

The value corresponding to the key.

Return Value

Type: System.Boolean

true if keyword was found within the connection string, false otherwise.

Exception Condition

keyword contains a null value (Nothing in Visual Basic).

The TryGetValue method lets developers safely retrieve a value from a DbConnectionStringBuilder without needing to first call the ContainsKey method. Because TryGetValue does not raise an exception when you call it, passing in a nonexistent key, you do not have to look for a key before retrieving its value. Calling TryGetValue with a nonexistent key will place the null value (Nothing in Visual Basic) in the value parameter.

The following example calls the TryGetValue method, demonstrating several possible outcomes.

static void Main()
    DbConnectionStringBuilder builder = new DbConnectionStringBuilder();
    builder.ConnectionString = 
        "Provider=sqloledb;Data Source=,1433;" +
        "Network Library=DBMSSOCN;Initial Catalog=pubs;" +
        "Integrated Security=SSPI;";

    // Call TryGetValue method for multiple
    // key names.
    DisplayValue(builder, "Provider");
    DisplayValue(builder, "DATA SOURCE");
    DisplayValue(builder, "InvalidKey");
    DisplayValue(builder, null);


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

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

The sample displays the following results:

Unable to retrieve value for //InvalidKey//
Unable to retrieve value for null key.

Universal Windows Platform
Available since 10
.NET Framework
Available since 2.0
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