DbConnectionStringBuilder.Add(String, Object) Method
Definition
Adds an entry with the specified key and value into the DbConnectionStringBuilder.
public:
void Add(System::String ^ keyword, System::Object ^ value);
public void Add (string keyword, object value);
member this.Add : string * obj -> unit
Public Sub Add (keyword As String, value As Object)
Parameters
- keyword
- String
The key to add to the DbConnectionStringBuilder.
- value
- Object
The value for the specified key.
Exceptions
keyword
is a null reference (Nothing
in Visual Basic).
Examples
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.
Note
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.
static void Main()
{
try
{
DbConnectionStringBuilder builder =
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(null, "Some Value");
Console.WriteLine(builder.ConnectionString);
}
catch (ArgumentNullException)
{
Console.WriteLine("Null key values are not allowed.");
}
Console.WriteLine("Press Enter to continue.");
Console.ReadLine();
}
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
Remarks
The Item[String] 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.