OleDbConnectionStringBuilder.Remove(String) 方法

定義

命名空間:
System.Data.OleDb
組件:
System.Data.dll

從實例中移除指定金鑰 OleDbConnectionStringBuilder 的條目。

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

參數

keyword
String

在此 OleDbConnectionStringBuilder 中，要從連接字串中移除的鍵/值對的鍵。

傳回

Boolean

true 如果金鑰存在於連接字串中且已被移除，false 若金鑰不存在。

例外狀況

ArgumentNullException

keyword 在 Visual Basic 中為空Nothing 。

範例

以下範例建立 並 OleDbConnectionStringBuilder 展示該 Remove 方法的行為。

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

備註

由於 Remove 方法回傳的值顯示其成功，因此在嘗試移除該鍵值對 OleDbConnectionStringBuilder 之前，不需要先尋找金鑰的存在。

適用於

另請參閱