IDbDataAdapter.DeleteCommand 属性

定义

命名空间:

System.Data

程序集:

netstandard.dll, System.Data.Common.dll

Source:

IDbDataAdapter.cs

获取或设置用于从数据集中删除记录的 SQL 语句。

public:
 property System::Data::IDbCommand ^ DeleteCommand { System::Data::IDbCommand ^ get(); void set(System::Data::IDbCommand ^ value); };

public System.Data.IDbCommand? DeleteCommand { get; set; }

member this.DeleteCommand : System.Data.IDbCommand with get, set

Public Property DeleteCommand As IDbCommand

属性值

IDbCommand

用于IDbCommandUpdate(DataSet)删除数据集中已删除行的数据源中的记录。

示例

以下示例创建继承 OleDbDataAdapter 类的实例，并设置 SelectCommand 和 DeleteCommand 属性。 它假定你已经创建了一个 OleDbConnection 对象。

public static OleDbDataAdapter CreateCustomerAdapter(
    OleDbConnection connection)
{
    OleDbDataAdapter dataAdapter = new OleDbDataAdapter();
    OleDbCommand command;
    OleDbParameter parameter;

    // Create the SelectCommand.
    command = new OleDbCommand("SELECT CustomerID FROM Customers " +
        "WHERE Country = ? AND City = ?", connection);

    command.Parameters.Add("Country", OleDbType.VarChar, 15);
    command.Parameters.Add("City", OleDbType.VarChar, 15);

    dataAdapter.SelectCommand = command;

    // Create the DeleteCommand.
    command = new OleDbCommand(
        "DELETE * FROM Customers WHERE CustomerID = ?",
        connection);

    parameter = command.Parameters.Add(
        "CustomerID", OleDbType.Char, 5, "CustomerID");
    parameter.SourceVersion = DataRowVersion.Original;

    dataAdapter.DeleteCommand = command;

    return dataAdapter;
}

Public Shared Function CreateCustomerAdapter( _
    connection As OleDbConnection) As OleDbDataAdapter 

    Dim dataAdapter As New OleDbDataAdapter()
    Dim command As OleDbCommand
    Dim parameter As OleDbParameter

    ' Create the SelectCommand.
    command = New OleDbCommand("SELECT CustomerID FROM Customers " & _
        "WHERE Country = ? AND City = ?", connection)

    command.Parameters.Add("Country", OleDbType.VarChar, 15)
    command.Parameters.Add("City", OleDbType.VarChar, 15)

    dataAdapter.SelectCommand = command

    ' Create the DeleteCommand.
    command = New OleDbCommand( _
        "DELETE * FROM Customers WHERE CustomerID = ?", _
        connection)

    parameter = command.Parameters.Add( _
        "CustomerID", OleDbType.Char, 5, "CustomerID")
    parameter.SourceVersion = DataRowVersion.Original

    dataAdapter.DeleteCommand = command

    Return dataAdapter
End Function

注解

在此期间 Update，如果未设置此属性并且主键信息存在于其中 DataSet， DeleteCommand 则可以在设置 SelectCommand .NET Framework 数据提供程序的属性时自动生成该属性。 然后，未设置的任何其他命令由 CommandBuilder 生成。 此生成逻辑要求关键列信息存在于 .DataSet 有关详细信息，请参阅 使用 CommandBuilders 生成命令。

分配给以前创建的DeleteCommand时IDbCommand，IDbCommand不会克隆。 维护 DeleteCommand 对以前创建 IDbCommand 对象的引用。