remove null column from collection in c#

Question

I have a table Menu and the data is like the attached screen shot Database table

and I want output like below image,

Means all the null values or integer ==0 should be hidden.

Right now I am showing these 5 columns only as you can see in 2nd screen shot..

I have something like this..

List<Menu> lstMenus = obj.GetMenus(10);

My code is

var menus = new List< dynamic >();

foreach (Menu menuBE in lstMenus)
    {

        dynamic menu = new
        {

            menuBE.MenuID,
            menuBE.ParentMenuID,
            menuBE.LinkText,
            menuBE.ScreenName,
            menuBE.Parameters,
            menuBE.URL
            // if(menuBE.Parameters.Length>0 ){ Parameters = menuBE.Parameters,}
        };
        menus.Add(menu);
    }

and I want to put some condition like the last commented line in foreach loop. If menuBE.Parameters.Length>0 then this Parameters column should add be in dynamic menu else not. Any idea how it can be done?

Answer 1

What I understood, in the opposite of James & techloverr, you want to keep records with parameter null:

foreach (Menu menuBE in lstMenus){
    if (menuBE.Parameters.Length > 0){
       dynamic menu = new{
           menuBE.MenuID,
           menuBE.ParentMenuID,
           menuBE.LinkText,
           menuBE.ScreenName,
           menuBE.Parameters,
           menuBE.URL
       };
    }
    else {
       dynamic menu = new{
           menuBE.MenuID,
           menuBE.ParentMenuID,
           menuBE.LinkText,
           menuBE.ScreenName,
           menuBE.URL
       };
    }
    menus.Add(menu);
}

** UPDATE **

As I understand in the whole question, you do not want a property Parameters when source data have Parameters.Lenght == 0, and that's why you are using dynamic type.

It's different from "that's OK have a property 'Parameters = null'". If that's the approach, you don't need to use dynamic type. Just add items as list-item of a declarated strong-type variable or list-item of anonymous type.

With the dynamic type you add properties at declaration time. So, you have to separate the different assigns as the code above. If you want to put if outside to avoid duplicate code, you use ExpandoObject:

var m = new List<System.Dynamic.ExpandoObject>();
foreach (string item in new string[] { "a", "b", "c" }) {
    dynamic menuItem = new System.Dynamic.ExpandoObject();

    menuItem.pos1 = item;
    menuItem.pos2 = (item == "b" ? item : null); // wrong

    if (item == "c") {           // correct
        menuItem.pos3 = "I am at third iteration";
    }

    m.Add(menuItem);
}

See, if you put a breakpoint at m.Add(menuItem); these are the results:
case item == "a":

menuItem.pos1 = "a";
menuItem.pos2 = null; // wrong: pos2 must not exists

case item == "b":

menuItem.pos1 = "b";
menuItem.pos2 = "b";

case item == "c":

menuItem.pos1 = "c";
menuItem.pos2 = null; // wrong: pos2 must not exists
menuItem.pos3 = "I am at third iteration"; // correct: pos3 only exists here.

Answer 2

you can use this code snippet

  foreach (Menu menuBE in lstMenus)
    {

        dynamic menu = new
        {

          MenuID = menuBE.MenuID,
          ParentMenuID =  menuBE.ParentMenuID,
          LinkText =  menuBE.LinkText,
          ScreenName = menuBE.ScreenName,

          URL = menuBE.URL,
            Parameters = (menuBE.Parameters.Length>0) ? menuBE.Parameters : null
        };
        menus.Add(menu);
    }