Question

You can create the same design but without the condition (if) ?

foreach (var item in ListItems)
{
    if(item.IsChecked)
    {
        //
    }
}

for example(not worked example):

foreach (var item in ListItems(=>IsCheked))
{
    //only IsChecked
}

c#-2.0 – not use linq

Answer 1

C# 3 and Framework 3.5:

foreach(var item in ListItems.Where(x => x.IsChecked))

C# 2 , Framework 2.0 (assuming ListItems is a List)

foreach(<type> item in ListItems.FindAll(delegate(x) { return x.IsChecked; }))

C# 3, Framework 2.0 (if you’re using visual studio 2008 or later but targeting 2.0 framework)
The lambda syntax and var keyword can be compiled, but there is no System.LINQ library to refer to.

foreach(var item in ListItems.FindAll(x => x.IsChecked))