OleDbConnectionStringBuilder 類別

定義

public ref class OleDbConnectionStringBuilder sealed : System::Data::Common::DbConnectionStringBuilder

[System.ComponentModel.TypeConverter(typeof(System.Data.OleDb.OleDbConnectionStringBuilder+OleDbConnectionStringBuilderConverter))]
public sealed class OleDbConnectionStringBuilder : System.Data.Common.DbConnectionStringBuilder

[<System.ComponentModel.TypeConverter(typeof(System.Data.OleDb.OleDbConnectionStringBuilder+OleDbConnectionStringBuilderConverter))>]
type OleDbConnectionStringBuilder = class
    inherit DbConnectionStringBuilder

Public NotInheritable Class OleDbConnectionStringBuilder
Inherits DbConnectionStringBuilder

繼承

Object

DbConnectionStringBuilder

OleDbConnectionStringBuilder

屬性

TypeConverterAttribute

範例

以下主控台應用程式為多個 OLE DB 資料庫建立連接字串。 首先，範例為 Microsoft Access 資料庫建立一個 連接字串，接著為 IBM DB2 資料庫建立一個 連接字串。 此範例也會剖析現有的連接字串，並示範各種操作連接字串內容的方式。

using System.Data.OleDb;

class Program
{
    static void Main(string[] args)
    {
        OleDbConnectionStringBuilder builder = new OleDbConnectionStringBuilder();
        builder.ConnectionString = @"Data Source=C:\Sample.mdb";

        // Call the Add method to explicitly add key/value
        // pairs to the internal collection.
        builder.Add("Provider", "Microsoft.Jet.Oledb.4.0");
        builder.Add("Jet OLEDB:Database Password", "MyPassword!");
        builder.Add("Jet OLEDB:System Database", @"C:\Workgroup.mdb");

        // Set up row-level locking.
        builder.Add("Jet OLEDB:Database Locking Mode", 1);

        Console.WriteLine(builder.ConnectionString);
        Console.WriteLine();

        // Clear current values and reset known keys to their
        // default values.
        builder.Clear();

        // Pass the OleDbConnectionStringBuilder an existing
        // connection string, and you can retrieve and
        // modify any of the elements.
        builder.ConnectionString =
            "Provider=DB2OLEDB;Network Transport Library=TCPIP;" +
            "Network Address=192.168.0.12;Initial Catalog=DbAdventures;" +
            "Package Collection=SamplePackage;Default Schema=SampleSchema;";

        Console.WriteLine("Network Address = " + builder["Network Address"].ToString());
        Console.WriteLine();

        // Modify existing items.
        builder["Package Collection"] = "NewPackage";
        builder["Default Schema"] = "NewSchema";

        // Call the Remove method to remove items from
        // the collection of key/value pairs.
        builder.Remove("User ID");

        // Note that calling Remove on a nonexistent item does not
        // throw an exception.
        builder.Remove("BadItem");
        Console.WriteLine(builder.ConnectionString);
        Console.WriteLine();

        // Setting the indexer adds the value, if
        // necessary.
        builder["User ID"] = "SampleUser";
        builder["Password"] = "SamplePassword";
        Console.WriteLine(builder.ConnectionString);

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

Imports System.Data.OleDb
Imports System.Collections

Module Module1
  Sub Main()
    Dim builder As New OleDbConnectionStringBuilder()
    builder.ConnectionString = "Data Source=C:\Sample.mdb"

    ' Call the Add method to explicitly add key/value
    ' pairs to the internal collection.
    builder.Add("Provider", "Microsoft.Jet.Oledb.4.0")
    builder.Add("Jet OLEDB:Database Password", "MyPassword!")
    builder.Add("Jet OLEDB:System Database", "C:\Workgroup.mdb")

    ' Set up row-level locking.
    builder.Add("Jet OLEDB:Database Locking Mode", 1)

    Console.WriteLine(builder.ConnectionString)
    Console.WriteLine()

    ' Clear current values and reset known keys to their
    ' default values.
    builder.Clear()

    ' Pass the OleDbConnectionStringBuilder an existing
    ' connection string, and you can retrieve and
    ' modify any of the elements.
    builder.ConnectionString = "..."

    Console.WriteLine("Network Address = " & builder("Network Address").ToString())
    Console.WriteLine()

    ' Modify existing items.
    builder("Package Collection") = "NewPackage"
    builder("Default Schema") = "NewSchema"

    ' Call the Remove method to remove items from
    ' the collection of key/value pairs.
    builder.Remove("User ID")

    ' Note that calling Remove on a nonexistent item does not
    ' throw an exception.
    builder.Remove("BadItem")
    Console.WriteLine(builder.ConnectionString)
    Console.WriteLine()

    ' The Item property is the default for the class,
    ' and setting the Item property adds the value, if
    ' necessary.
    builder("User ID") = "SampleUser"
    builder("Password") = "SamplePassword"
    Console.WriteLine(builder.ConnectionString)

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

備註

連接字串產生器可讓開發人員使用 類別的屬性和方法，以程式設計方式建立語法正確的連接字串，以及剖析和重建現有的連接字串。 連接字串 建構器提供強型別屬性，對應於 OLE DB 連線允許的已知鍵值對，開發者可為任何其他 連接字串 值加入任意鍵值對。 OleDbConnectionStringBuilder 類別會實作 ICustomTypeDescriptor 介面。 這表示課程在設計時會與Visual Studio .NET設計師合作。 當開發者使用 Designer 在 Visual Studio .NET 內建立強型別的 DataSets 與強型別的連接時，強型別的 連接字串 建構器類別會顯示其型別相關的屬性，並具備可映射已知鍵值的轉換器。

需要在應用程式中建立連接字串的開發者，可以使用此 OleDbConnectionStringBuilder 類別來建構和修改連接字串。 類別也可讓您輕鬆地管理儲存在應用程式組態檔中的連接字串。 它 OleDbConnectionStringBuilder 僅對有限的已知鍵值對進行檢查。 因此，這個類別可以用來建立無效的連接字串。 下表列出已知的鍵及其在類別中 OleDbConnectionStringBuilder 對應的屬性，以及它們的預設值。 除了這些特定值外，開發者還可以將任何鍵值對加入實例內 OleDbConnectionStringBuilder 的集合中：

Item[] 屬性會處理嘗試插入惡意專案。 例如，下列程式代碼會使用預設 Item[] 屬性（以 C# 表示索引器）正確地逸出巢狀索引鍵/值組：

Dim builder As _
    New System.Data.OleDb.OleDbConnectionStringBuilder
builder("Provider") = "Microsoft.Jet.OLEDB.4.0"
builder("Data Source") = "C:\Sample.mdb"
builder("User Id") = "Admin;NewValue=Bad"

System.Data.OleDb.OleDbConnectionStringBuilder builder =
    new System.Data.OleDb.OleDbConnectionStringBuilder();
builder["Provider"] = "Microsoft.Jet.OLEDB.4.0";
builder["Data Source"] = "C:\\Sample.mdb";
builder["User Id"] = "Admin;NewValue=Bad";

結果是下列連接字串，會以安全的方式處理無效的值：

Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Sample.mdb;User ID="Admin;NewValue=Bad"

另請參閱

• 連接字串產生器
• ADO.NET 中的連接字串