private void InitData()
{
DataSet myDs=new DataSet();
//主表
Role role=new Role();
DataTable roleDt = role.GetRoles();
roleDt.TableName = "Role";
myDs.Tables.Add(roleDt);
//从表
User user = new User();
DataTable userDt = user.GetAllUsers();
userDt.TableName = "User";
myDs.Tables.Add(userDt);
DataColumn keyColumn = myDs.Tables["Role"].Columns["roleId"]; //主键
DataColumn foreignColumn = myDs.Tables["User"].Columns["roleId"]; //外键
///
///对于主从表,层次名至关重要,关系名必须和从表的层次名一致,
///否则从表显示的是从表的所有字段,而不是所设计的显示字段
///
myDs.Relations.Add("UserView", keyColumn, foreignColumn); //从表的层次名
grcMain.DataSource = myDs.Tables["Role"];
}