SqlConnection 建構函式

定義

初始化 SqlConnection 類別的新執行個體。

多載

名稱 Description
SqlConnection()

初始化 SqlConnection 類別的新執行個體。

SqlConnection(String)

當給定包含連接字串的字串時,初始化該類別的新 SqlConnection 實例。

SqlConnection(String, SqlCredential)

初始化一個新實例, SqlConnection 給定一個不使用 Integrated Security = true 包含使用者 ID 和密碼的連接字串和 SqlCredential 物件。

SqlConnection()

初始化 SqlConnection 類別的新執行個體。

public:
 SqlConnection();
public SqlConnection();
Public Sub New ()

範例

以下範例創建並開啟一個 SqlConnection

private static void OpenSqlConnection()
{
    string connectionString = GetConnectionString();
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();
        Console.WriteLine("ServerVersion: {0}", connection.ServerVersion);
        Console.WriteLine("State: {0}", connection.State);
    }
}

static private string GetConnectionString()
{
    // To avoid storing the connection string in your code,
    // you can retrieve it from a configuration file, using the
    // System.Configuration.ConfigurationManager.ConnectionStrings property
    return "Data Source=(local);Initial Catalog=AdventureWorks;"
        + "Integrated Security=SSPI;";
}
Private Sub OpenSqlConnection()
    Dim connectionString As String = GetConnectionString()
    Using connection As New SqlConnection(connectionString)
        connection.Open()
        Console.WriteLine("ServerVersion: {0}", connection.ServerVersion)
        Console.WriteLine("State: {0}", connection.State)
    End Using
End Sub

Private Function GetConnectionString() As String
    ' To avoid storing the connection string in your code,  
    ' you can retrieve it from a configuration file, using the
    ' System.Configuration.ConfigurationManager.ConnectionStrings property
    Return "Data Source=(local);Database=AdventureWorks;" _
      & "Integrated Security=SSPI;"
End Function

備註

當建立新的 實例時 SqlConnection ,除非這些屬性特別使用屬性中 ConnectionString 對應的關鍵字設定,否則讀寫屬性會設定為以下初始值。

屬性 初始值
ConnectionString 空字串(“”
ConnectionTimeout 15
Database 空字串(“”
DataSource 空字串(“”

你只能透過使用屬性來 ConnectionString 更改這些屬性的值。 這個 SqlConnectionStringBuilder 類別提供建立和管理連接字串內容的功能。

另請參閱

適用於

SqlConnection(String)

當給定包含連接字串的字串時,初始化該類別的新 SqlConnection 實例。

public:
 SqlConnection(System::String ^ connectionString);
public SqlConnection(string connectionString);
new System.Data.SqlClient.SqlConnection : string -> System.Data.SqlClient.SqlConnection
Public Sub New (connectionString As String)

參數

connectionString
String

用來開啟 SQL Server 資料庫的連線。

例外狀況

所提供的連接字串參數驗證失敗 ConnectionString

範例

以下範例創建並開啟一個 SqlConnection

private static void OpenSqlConnection()
{
    string connectionString = GetConnectionString();

    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();

        Console.WriteLine("State: {0}", connection.State);
        Console.WriteLine("ConnectionString: {0}",
            connection.ConnectionString);
    }
}

static private string GetConnectionString()
{
    // To avoid storing the connection string in your code,
    // you can retrieve it from a configuration file, using the
    // System.Configuration.ConfigurationSettings.AppSettings property
    return "Data Source=(local);Initial Catalog=AdventureWorks;"
        + "Integrated Security=SSPI;";
}
Private Sub OpenSqlConnection()
    Dim connectionString As String = GetConnectionString()

    Using connection As New SqlConnection(connectionString)

        connection.Open()

        Console.WriteLine("State: {0}", connection.State)
        Console.WriteLine("ConnectionString: {0}", _
            connection.ConnectionString)
    End Using
End Sub

Private Function GetConnectionString() As String
    ' To avoid storing the connection string in your code,  
    ' you can retrieve it from a configuration file, using the
    ' System.Configuration.ConfigurationSettings.AppSettings property
    Return "Data Source=(local);Database=AdventureWorks;" _
      & "Integrated Security=SSPI;"
End Function

備註

當建立新的 實例時 SqlConnection ,除非這些屬性特別使用屬性中 ConnectionString 對應的關鍵字設定,否則讀寫屬性會設定為以下初始值。

屬性 初始值
ConnectionString connectionString
ConnectionTimeout 15
Database 空字串(“”
DataSource 空字串(“”

你只能透過使用屬性來 ConnectionString 更改這些屬性的值。 這個 SqlConnection 類別提供建立和管理連接字串內容的功能。

另請參閱

適用於

SqlConnection(String, SqlCredential)

初始化一個新實例, SqlConnection 給定一個不使用 Integrated Security = true 包含使用者 ID 和密碼的連接字串和 SqlCredential 物件。

public:
 SqlConnection(System::String ^ connectionString, System::Data::SqlClient::SqlCredential ^ credential);
public SqlConnection(string connectionString, System.Data.SqlClient.SqlCredential credential);
new System.Data.SqlClient.SqlConnection : string * System.Data.SqlClient.SqlCredential -> System.Data.SqlClient.SqlConnection
Public Sub New (connectionString As String, credential As SqlCredential)

參數

connectionString
String

一個不使用以下任何連接字串關鍵字 Integrated Security = true的連接字串:、、 UserIdPassword;或不使用 ContextConnection = true

credential
SqlCredential

SqlCredential 物件。 若 credential 為空, SqlConnection(String, SqlCredential) 則在功能上等價於 SqlConnection(String)

例外狀況

所提供的連接字串參數驗證失敗 ConnectionString

另請參閱

適用於