da.InsertCommand = cmd

  '''' Create the DeleteCommand.

  cmd = New OleDbCommand("DELETE FROM Customers WHERE CustomerID = @CustomerID", conn)

  parm = cmd.Parameters.Add("@CustomerID", OleDbType.Char, 5, "CustomerID")

  parm.SourceVersion = DataRowVersion.Original

  da.DeleteCommand = cmd

  '''' Create the UpdateCommand.

  cmd = New OleDbCommand("UPDATE Customers SET CustomerID = @CustomerID, CompanyName = @CompanyName WHERE CustomerID = @oldCustomerID", conn)

  cmd.Parameters.Add("@CustomerID", OleDbType.Char, 5, "CustomerID")

  cmd.Parameters.Add("@CompanyName", OleDbType.VarChar, 40, "CompanyName")

  parm = cmd.Parameters.Add("@oldCustomerID", OleDbType.Char, 5, "CustomerID")

  parm.SourceVersion = DataRowVersion.Original

  da.UpdateCommand = cmd

  Return da

End Function

以下两行

parm = cmd.Parameters.Add("@CustomerID", OleDbType.Char, 5, "CustomerID")

parm.SourceVersion = DataRowVersion.Original

可以缩写为

cmd.Parameters.Add("@CustomerID", OleDbType.Char, 5, "CustomerID").SourceVersion = DataRowVersion.Original

类似地当添加参数后马上进行设置参数的值时,也可以进行类似以下缩写

myDataAdapter.SelectCommand.Parameters.Add("@CategoryName", OleDbType.VarChar, 80).Value = "toasters"

myDataAdapter.SelectCommand.Parameters.Add("@SerialNum", OleDbType.Integer).Value = 239

(信息整理来自MSDN)

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