SqlCeDataAdapter 构造函数 ()
初始化 SqlCeDataAdapter 类的新实例。
命名空间: System.Data.SqlServerCe
程序集: System.Data.SqlServerCe(在 system.data.sqlserverce.dll 中)
语法
声明
Public Sub New
用法
Dim instance As New SqlCeDataAdapter
public SqlCeDataAdapter ()
public:
SqlCeDataAdapter ()
public SqlCeDataAdapter ()
public function SqlCeDataAdapter ()
不适用。
备注
当创建 SqlCeDataAdapter 的实例时,下面的读/写属性将设置为以下初始值。
属性 |
初始值 |
---|---|
MissingMappingAction.Passthrough |
|
MissingSchemaAction.Add |
可以通过单独调用这些属性中某个属性来更改该属性的值。
示例
下面的示例创建一个 SqlCeDataAdapter 并设置它的一些属性。
Dim cmd As SqlCeCommand = Nothing
Dim adp As SqlCeDataAdapter = Nothing
Try
adp = New SqlCeDataAdapter()
Dim conn As New SqlCeConnection("Data Source = MyDatabase.sdf")
' Create the SelectCommand
'
cmd = conn.CreateCommand()
cmd.CommandText = "SELECT [Employee ID], [First Name], [Last Name] FROM Employees"
adp.SelectCommand = cmd
' Create the InsertCommand
'
cmd = conn.CreateCommand()
cmd.CommandText = "INSERT INTO Employees ([First Name],[Last Name]) VALUES (@first, @last)"
Dim p As SqlCeParameter = Nothing
p = cmd.Parameters.Add("@first", SqlDbType.NVarChar, 10, "First Name")
p.SourceVersion = DataRowVersion.Original
p = cmd.Parameters.Add("@last", SqlDbType.NVarChar, 20, "Last Name")
p.SourceVersion = DataRowVersion.Original
adp.InsertCommand = cmd
' Create the UpdateCommand
'
cmd = conn.CreateCommand()
cmd.CommandText = "UPDATE Employees SET [First Name] = @first, " + _
"[Last Name] = @last WHERE [Employee ID] = @employeeID"
p = cmd.Parameters.Add("@first", SqlDbType.NVarChar, 10, "First Name")
p.SourceVersion = DataRowVersion.Current
p = cmd.Parameters.Add("@last", SqlDbType.NVarChar, 20, "Last Name")
p.SourceVersion = DataRowVersion.Current
p = cmd.Parameters.Add("@employeeID", SqlDbType.NVarChar, 20, "Employee ID")
p.SourceVersion = DataRowVersion.Original
adp.UpdateCommand = cmd
' Populate the dataset with the results from the SELECT statement
'
Dim ds As New DataSet()
adp.Fill(ds)
' Modify the dataset
'
MessageBox.Show("Number of rows: " & ds.Tables(0).Rows.Count)
' Insert some rows
'
ds.Tables(0).Rows.Add(New Object() {Nothing, "Nancy", "Smith"})
ds.Tables(0).Rows.Add(New Object() {Nothing, "Joe", "Clayton"})
' Update some rows
'
ds.Tables(0).Rows(1)(1) = "David"
ds.Tables(0).Rows(1)(2) = "Johnson"
' This will execute two INSERT and one UPDATE statements
'
adp.Update(ds.Tables(0))
Catch e As Exception
MessageBox.Show(e.Message)
Finally
If Not Nothing Is adp.SelectCommand Then
adp.SelectCommand.Dispose()
End If
If Not Nothing Is adp.InsertCommand Then
adp.InsertCommand.Dispose()
End If
End Try
SqlCeCommand cmd = null;
SqlCeDataAdapter adp = null;
try
{
adp = new SqlCeDataAdapter();
SqlCeConnection conn = new SqlCeConnection("Data Source = MyDatabase.sdf");
// Create the SelectCommand
//
cmd = conn.CreateCommand();
cmd.CommandText = "SELECT [Employee ID], [First Name], [Last Name] FROM Employees";
adp.SelectCommand = cmd;
// Create the InsertCommand
//
cmd = conn.CreateCommand();
cmd.CommandText = "INSERT INTO Employees ([First Name],[Last Name]) VALUES (@first, @last)";
SqlCeParameter p = null;
p = cmd.Parameters.Add("@first", SqlDbType.NVarChar, 10, "First Name");
p.SourceVersion = DataRowVersion.Original;
p = cmd.Parameters.Add("@last", SqlDbType.NVarChar, 20, "Last Name");
p.SourceVersion = DataRowVersion.Original;
adp.InsertCommand = cmd;
// Create the UpdateCommand
//
cmd = conn.CreateCommand();
cmd.CommandText = "UPDATE Employees SET [First Name] = @first, " +
"[Last Name] = @last WHERE [Employee ID] = @employeeID";
p = cmd.Parameters.Add("@first", SqlDbType.NVarChar, 10, "First Name");
p.SourceVersion = DataRowVersion.Current;
p = cmd.Parameters.Add("@last", SqlDbType.NVarChar, 20, "Last Name");
p.SourceVersion = DataRowVersion.Current;
p = cmd.Parameters.Add("@employeeID", SqlDbType.NVarChar, 20, "Employee ID");
p.SourceVersion = DataRowVersion.Original;
adp.UpdateCommand = cmd;
// Populate the dataset with the results from the SELECT statement
//
DataSet ds = new DataSet();
adp.Fill(ds);
// Modify the dataset
//
MessageBox.Show("Number of rows: " + ds.Tables[0].Rows.Count);
// Insert some rows
//
ds.Tables[0].Rows.Add(new object[] { null, "Nancy", "Smith" });
ds.Tables[0].Rows.Add(new object[] { null, "Joe", "Clayton" });
// Update some rows
//
ds.Tables[0].Rows[1][1] = "David";
ds.Tables[0].Rows[1][2] = "Johnson";
// This will execute two INSERT and one UPDATE statements
//
adp.Update(ds.Tables[0]);
}
catch (Exception e)
{
MessageBox.Show(e.Message);
}
finally
{
if (null != adp.SelectCommand) adp.SelectCommand.Dispose();
if (null != adp.InsertCommand) adp.InsertCommand.Dispose();
}
平台
Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
Windows Vista、Microsoft Windows XP SP2 和 Windows Server 2003 SP1 支持 Microsoft .NET Framework 3.0。
版本信息
.NET Framework
受以下版本支持:3.0
.NET Compact Framework
受以下版本支持:2.0、1.0
请参见
参考
SqlCeDataAdapter 类
SqlCeDataAdapter 成员
System.Data.SqlServerCe 命名空间
MissingMappingAction
MissingSchemaAction