请教"Fill: SelectCommand.Connection 属性尚未初始化" 错误

[hwa_Jue]

代码如下,运行时报:Fill: SelectCommand.Connection 属性尚未初始化。

private void Button_Submit_Click(object sender, System.EventArgs e)
{

OracleConnection cnConnection =new OracleConnection("user id=doc;data source=connect;Password=123");
cnConnection.Open();
OracleCommand cnCommand = new OracleCommand("SELECT TYPECODE,TYPENAME FROM DD_DOC_TYPE");
OracleDataAdapter cnAdapter= new OracleDataAdapter(cnCommand);
DataSet DS = new DataSet();
cnAdapter.Fill(DS);

DataGrid1.DataSource=DS;
DataGrid1.DataBind();
cnConnection.Close();

}

[saucer]

OracleCommand cnCommand = new OracleCommand("SELECT TYPECODE,TYPENAME FROM DD_DOC_TYPE");
===>

OracleCommand cnCommand = new OracleCommand("SELECT TYPECODE,TYPENAME FROM DD_DOC_TYPE", cnConnection);

or
cnCommand.Connection = cnConnection;