How to retrieve database data on selected attribute with foreach loop?RSS

• • Reply
  emirryhn

  Member

  4 Points

  21 Posts

  How to retrieve database data on selected attribute with foreach loop?

  May 30, 2020 06:40 AM|emirryhn|LINK

  Hi, i want to know how to listed/retrieve data from selected database table with foreach loop, but without showing ALL data instead i want to show selected data only. 

  Example on html syntax, call it MenuList.cshtml

         @foreach (var item in Model.Menu)
          {
              <tr>
                  <td>
                      @Html.DisplayFor(modelItem => item.Breakfast)
                  </td>

  DbController.cs

          public static List<Menu> LoadMenu()
          {
              string sql = @"select MenuID, Breakfast from dbo.Menu;";
  
              return SqlDataAccess.LoadData<Menu>(sql);
          }

  MenuList.cshtml.cs

          public ActionResult ViewMenu()
          {
              ViewBag.Message = "Menu List";
  
              var data = LoadMenu();
              List<Menu> menu = new List<Menu>();
  
              foreach(var row in data)
              {
                  menu.Add(new Menu
                  {
                      Breakfast = row.Breakfast
                  });
              }
              return Page();
          }

  In Menu.cs, i provided 3 data in Breakfast attribute. I would like to show only 1 from 3 data. How should i limit the foreach loop?

• • Reply
  PaulTheSmith

  Participant

  1290 Points

  717 Posts

  Re: How to retrieve database data on selected attribute with foreach loop?

  Jun 01, 2020 12:43 AM|PaulTheSmith|LINK

  Change your sql so it only retrieves the rows that you want.

  select MenuID, Breakfast from dbo.Menu where ….

• • Reply
  yogyogi

  Participant

  1100 Points

  849 Posts

  Re: How to retrieve database data on selected attribute with foreach loop?

  Jun 01, 2020 06:02 AM|yogyogi|LINK

  You could use a LINQ query with Where condition after this something like:

  SqlDataAccess.LoadData<Menu>(sql).Where(t => t.Name =="Jack");

  Helping you always. Don't forget to click "Mark as Answer" on the post that helped you.
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• • Reply
  YihuiSun

  Member

  470 Points

  203 Posts

  Re: How to retrieve database data on selected attribute with foreach loop?

  Jun 01, 2020 08:35 AM|YihuiSun|LINK

  Hi,  emirryhn

  You can use "if" in your loop to judge based on a certain condition.

  data.ForEach(m =>
  {
       if (m.MenuID == 1)
       {
            menu.Add(new Menu { Breakfast = m.Breakfast });
       }
  });

  OR

  foreach (var row in data)
              {
                  if (row.MenuID == 1)
                  {
                      menu.Add(new Menu
                      {
                          Breakfast = row.Breakfast
                      });
               }
  }

  Here is the result.

   
  Best Regards,

  YihuiSun