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OleDbConnectionStringBuilder.Remove(String) Method

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Definition

Namespace:
System.Data.OleDb
Assembly:
System.Data.OleDb.dll
Assembly:
System.Data.dll
Package:
System.Data.OleDb v9.0.0
Source:
OleDbConnectionStringBuilder.cs
Source:
OleDbConnectionStringBuilder.cs
Source:
OleDbConnectionStringBuilder.cs

Removes the entry with the specified key from the OleDbConnectionStringBuilder instance.

public:
 override bool Remove(System::String ^ keyword);
public override bool Remove (string keyword);
override this.Remove : string -> bool
Public Overrides Function Remove (keyword As String) As Boolean

Parameters

keyword
String

The key of the key/value pair to be removed from the connection string in this OleDbConnectionStringBuilder.

Returns

Boolean

true if the key existed within the connection string and was removed, false if the key did not exist.

Exceptions

ArgumentNullException

keyword is null (Nothing in Visual Basic).

Examples

The following example creates a OleDbConnectionStringBuilder and demonstrates the behavior of the Remove method.

using System.Data.OleDb;

class Program
{
    static void Main()
    {
        OleDbConnectionStringBuilder builder =
            new OleDbConnectionStringBuilder();
        builder.ConnectionString =
            "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\\Sample.mdb;" +
            "Jet OLEDB:System Database=C:\\system.mdw;";

        Console.WriteLine(builder.ConnectionString);

        // Try to remove an existing item.
        TryRemove(builder, "Provider");

        // Try to remove a nonexistent item.
        TryRemove(builder, "User ID");

        // try to remove an existing item,
        // demonstrating that the search isn't
        // case sensitive.
        TryRemove(builder, "DATA SOURCE");

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

    static void TryRemove(OleDbConnectionStringBuilder builder,
        string itemToRemove)
    {

        if (builder.Remove(itemToRemove))
        {
            Console.WriteLine("Removed '{0}'", itemToRemove);
        }
        else
        {
            Console.WriteLine("Unable to remove '{0}'", itemToRemove);
        }
        Console.WriteLine(builder.ConnectionString);
    }
}

Imports System.Data.OleDb    

Module Module1

  Sub Main()
    Dim builder As New OleDbConnectionStringBuilder
    builder.ConnectionString = _
        "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Sample.mdb;" & _
        "Jet OLEDB:System Database=C:\system.mdw;"

    Console.WriteLine(builder.ConnectionString)
    ' Try to remove an existing item.
    TryRemove(builder, "Provider")

    ' Try to remove a nonexistent item.
    TryRemove(builder, "User ID")

    ' Try to remove an existing item, 
    ' demonstrating that the search is not 
    ' case sensitive.
    TryRemove(builder, "DATA SOURCE")

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

  Sub TryRemove(ByVal builder As OleDbConnectionStringBuilder, _
      ByVal itemToRemove As String)

    If builder.Remove(itemToRemove) Then
      Console.WriteLine("Removed '{0}'", itemToRemove)
    Else
      Console.WriteLine("Unable to remove '{0}'", itemToRemove)
    End If
    Console.WriteLine(builder.ConnectionString)
  End Sub

End Module

Remarks

Because the Remove method returns a value that indicates its success, it is not required to look for the existence of a key before trying to remove the key/value pair from the OleDbConnectionStringBuilder instance.

Applies to

See also