如:
Dim MyConnection As New SqlConnection("ConnectionString")
Dim MyCommand As New SqlCommand("StoreProcedure", MyConnection)
MyCommand.CommandType = CommandType.StoredProcedure
Dim MyDataAdapter As New SqlDataAdapter(MyCommand)
Dim MyDataSet As New DataSet上述的MyConnection、MyCommand、MyDataAdapter、MyDataSet需要显式的调用Close方法关闭或将其设置为Nothing吗?
Dim MyConnection As New SqlConnection("ConnectionString")
Dim MyCommand As New SqlCommand("StoreProcedure", MyConnection)
MyCommand.CommandType = CommandType.StoredProcedure
Dim MyDataAdapter As New SqlDataAdapter(MyCommand)
Dim MyDataSet As New DataSet上述的MyConnection、MyCommand、MyDataAdapter、MyDataSet需要显式的调用Close方法关闭或将其设置为Nothing吗?
向你推荐一个好的视频教程吧!
http://www.microsoft.com/china/msdn/events/webcasts/shared/webcast/episode.aspx?newsID=1242164
是微软msdn特邀讲师讲的。比上培训班要强得多了。
特别提示:DataReader对象一定要显示的关闭
'Catalog.vb
Public Class Catalog Private Shared ReadOnly Property connectionString() As String
Get
Return ConfigurationSettings.AppSettings("ConnectionString")
End Get
End Property Public Shared Function GetDepartments() As SqlDataReader
Dim connection As New SqlConnection(connectionString)
Dim command As New SqlCommand("GetDepartments", connection)
command.CommandType = CommandType.StoredProcedure
connection.Open()
Return command.ExecuteReader(CommandBehavior.CloseConnection)
End FunctionEnd Class'a.aspx
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
If Not IsPostBack Then
DataGrid1.DataSource = Catalog.GetDepartments()
DataGrid1.DataBind()
End If
End Sub