C# – How to loop through all XElement attributes and get their values

Ian Mercer posted a similar solution as this on Phil Haack's blog:

foreach (var item in Model.Select((value, i) => new { i, value }))
{
    var value = item.value;
    var index = item.i;
}

This gets you the item (item.value) and its index (item.i) by using this overload of LINQ's Select:

the second parameter of the function [inside Select] represents the index of the source element.

The new { i, value } is creating a new anonymous object.

Heap allocations can be avoided by using ValueTuple if you're using C# 7.0 or later:

foreach (var item in Model.Select((value, i) => ( value, i )))
{
    var value = item.value;
    var index = item.i;
}

You can also eliminate the item. by using automatic destructuring:

<ol>
foreach ((MyType value, Int32 i) in Model.Select((value, i) => ( value, i )))
{
    <li id="item_@i">@value</li>
}
</ol>

• In case of a value type use Activator.CreateInstance and it should work fine.
• When using reference type just return null

public static object GetDefault(Type type)
{
   if(type.IsValueType)
   {
      return Activator.CreateInstance(type);
   }
   return null;
}

In the newer version of .net such as .net standard, type.IsValueType needs to be written as type.GetTypeInfo().IsValueType