Export (0) Print
Expand All

DbConnectionStringBuilder.Add Method

Adds an entry with the specified key and value into the DbConnectionStringBuilder.

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

'Declaration
Public Sub Add ( _
	keyword As String, _
	value As Object _
)

Parameters

keyword
Type: System.String

The key to add to the DbConnectionStringBuilder.

value
Type: System.Object

The value for the specified key.

ExceptionCondition
ArgumentNullException

keyword is a null reference (Nothing in Visual Basic).

NotSupportedException

The DbConnectionStringBuilder is read-only.

-or-

The DbConnectionStringBuilder has a fixed size.

The Item property can also be used to add new elements by setting the value of a key that does not exist in the dictionary. For example: myCollection["myNonexistentKey"] = myValue.

Calling the Add method by passing a null (Nothing in Visual Basic) key throws an ArgumentNullException. However, calling the Add method by passing a null value removes the key/value pair.

The following example creates a new DbConnectionStringBuilder and adds items. The code also demonstrates overwriting an existing item using the Add method, and includes a commented block that would throw an ArgumentNullException.

NoteNote

This example includes a password to demonstrate how DbConnectionStringBuilder works with connection strings. In your applications, we recommend that you use Windows Authentication. If you must use a password, do not include a hard-coded password in your application.

Sub Main()
    Try 
        Dim builder As New DbConnectionStringBuilder
        builder.Add("Data Source", "ServerName")
        builder.Add("Initial Catalog", "TheDatabase")
        builder.Add("User ID", "UserName")
        builder.Add("Password", "*******")
        builder.Add("Command Logging", False)

        ' Overwrite the existing "User ID" value.
        builder.Add("User ID", "NewUserName")

        ' The following code would trigger  
        ' an ArgumentNullException. 
        ' builder.Add(Nothing, "Some Value")

        Console.WriteLine(builder.ConnectionString)

    Catch ex As ArgumentNullException
        Console.WriteLine("Null key values are not allowed.")
    End Try

    Console.WriteLine("Press Enter to continue.")
    Console.ReadLine()
End Sub

.NET Framework

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

.NET Framework Client Profile

Supported in: 4, 3.5 SP1
Show:
© 2015 Microsoft