在MVC4 Resp API上获取错误“ IndexOutOfRangeExceptionwasunhandled”

Question

i am new in c#, and making a Restful API on MVC4, i am using following code and gets an error on

" foreach (DataRow menuDR in menuDataSet.Tables [7].Rows)"

IndexOutOfRangeException was unhandled by user code, and in details in show "cannot find table7" i used the same approach with 1 table database

foreach (DataRow menuDR in menuDataSet.Tables [0].Rows)

and it was working,now i have 8 tables in database, i don't know how to handle this exception and tried various things to get it sort....

public IEnumerable<RestaurantsMenu> GetAllMenu()
{
menuCon = new SqlConnection ("Data Source=MyPc\\MyPc;Initial Catalog=MENU;Integrated Security=True");
menuDataAdapter = new SqlDataAdapter (" SELECT * FROM RestaurantsMenu ", menuCon);
foreach (DataRow menuDR in menuDataSet.Tables [7].Rows)
{
Rst_Menu.Add(new RestaurantsMenu(){Restaurant_ID = int .Parse (menuDR[0].ToString()), RestaurantName =menuDR[1].ToString(),
Menu =menuDR[2].ToString(), Price=int .Parse (menuDR[3].ToString()) } );
}
return Rst_Menu;
}

Answer 1

Problem : you are querying only single table (table index 0) data from Database and trying to access table with index 7 which is not available.

even though there are 8 tables in your database following query does not give you all 8 tables data which will only give you the table data with index zero.

SELECT * FROM RestaurantsMenu

Solution : with the above select statement you should always referto Tables[0] as you get only single table.

Try This: to get mutiple tables

SqlDataAdapter menuDataAdapter = new SqlDataAdapter("SELECT * FROM RestaurantsMenu1;       "SELECT * FROM RestaurantsMenu2;"SELECT * FROM RestaurantsMenu3;", connection);
menuDataAdapter.TableMappings.Add("Table1", "RestaurantsMenu1");
menuDataAdapter.TableMappings.Add("Table2", "RestaurantsMenu2");
menuDataAdapter.TableMappings.Add("Table3", "RestaurantsMenu3");
for(int i=0;i<menuDataSet.Tables.Count;i++)
{
  foreach (DataRow menuDR in menuDataSet.Tables[i].Rows)
  {
    Rst_Menu.Add(new RestaurantsMenu(){Restaurant_ID = int .Parse (menuDR[0].ToString()), RestaurantName =menuDR[1].ToString(),
    Menu =menuDR[2].ToString(), Price=int .Parse (menuDR[3].ToString()) } );
  }
}