Question

如何将DataTable保存到文件中。 accdb（Access）现有的？我使用了以下代码，但它不起作用：

using (OleDbConnection oledbConnection = new OleDbConnection(connection))
{
   oledbConnection.Open();
   string query = "SELECT * FROM Student";
   using (OleDbCommand oledbCommand = new OleDbCommand(query, oledbConnection))
   {
      using (OleDbDataAdapter oledbDataAdapter = new OleDbDataAdapter(oledbCommand))
      {
         using (OleDbCommandBuilder oledbCommandBuilder = new OleDbCommandBuilder(oledbDataAdapter))
         {
            oledbDataAdapter.DeleteCommand = oledbCommandBuilder.GetDeleteCommand(true);
            oledbDataAdapter.InsertCommand = oledbCommandBuilder.GetInsertCommand(true);
            oledbDataAdapter.UpdateCommand = oledbCommandBuilder.GetUpdateCommand(true);
            oledbDataAdapter.Update(dataTable);
         }
      }
   }
   oledbConnection.Close();
}

使用文件的原始内容初始化变量dataTable，然后通过添加一行来修改它，现在我必须更新数据库中的表。

我尝试使用以下代码，但这不起作用：（

OleDbDataAdapter da = new OleDbDataAdapter("SELECT * FROM Student", connection);
OleDbCommandBuilder cmdBuilder = new OleDbCommandBuilder(da);
da.InsertCommand = cmdBuilder.GetInsertCommand(true);
// create and insert row in the DataTable
da.Update(dataTable);

Answer 1

假设您已对数据表进行了一些更改，那么您可以通过这种方式将生成的update / insert / delete命令传递给适配器

oledbDataAdapter.DeleteCommand = oledbCommandBuilder.GetDeleteCommand();
oledbDataAdapter.InsertCommand = oledbCommandBuilder.GetInsertCommand();
oledbDataAdapter.UpdateCommand = oledbCommandBuilder.GetUpdateCommand();
oledbDataAdapter.Update(datatable);

现在适配器知道如何更新表

C＃DataTable更新Access数据库

1 个答案: