从子行检索数据时出现错误。基本上我需要lecturerNamefrom tbl_lecturer，projectTitlefrom tbl_lecturer_project。
这是我的代码。
//get data from 3 tables
DataSet ds = new DataSet(); // .xsd file name
DataTable dt = new DataTable();
//Connection string replace 'databaseservername' with your db server name
SqlConnection con = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand();
SqlDataAdapter adapter;
con.Open();
//Stored procedure calling. It is already in sample db.
string selectSQL = "SELECT * FROM tbl_allocated_project where allocatedGroupId='" + team + "'";
cmd = new SqlCommand(selectSQL, con);
ds = new DataSet();
adapter = new SqlDataAdapter(cmd);
adapter.Fill(ds, "tbl_allocated_project");
cmd.CommandText = "SELECT * FROM tbl_lecturer_project";
adapter.Fill(ds, "tbl_lecturer_project");
cmd.CommandText = "SELECT * FROM tbl_lecturer";
adapter.Fill(ds, "tbl_lecturer");
DataRelation dr1 = new DataRelation("dr1", ds.Tables["tbl_lecturer"].Columns["lecturerId"],ds.Tables["tbl_lecturer_project"].Columns["lecturerId"]);
DataRelation dr2 = new DataRelation("dr2", ds.Tables["tbl_lecturer_project"].Columns["lecturerProjectId"], ds.Tables["tbl_allocated_project"].Columns["allocatedProjectId"]);
ds.Relations.Add(dr1);
ds.Relations.Add(dr2);
foreach (DataRow row in ds.Tables["tbl_allocated_project"].Rows)
{
lblDisplay.Text = "";
//lblDisplay.Text += row["allocatedGroupId"];
//lblDisplay.Text += " " + row["intro"];
foreach (DataRow col in row.GetChildRows(dr2))
{
DataRow rowdata = col.GetParentRows(dr1)[0];
//lblDisplay.Text += " ";
lblDisplay.Text += rowdata["projectTitle"];
}
}
我收到此错误：
GetChildRows 需要其表为 的行
tbl_lecturer_project，但指定行的表为tbl_allocated_project。
请帮忙。