>>>Hi All, is it possible in a "Linq type way" to set properties of class instances which are in a IList ? , for example I have a list of names and addresses in a list and if there are some that share a certain residential area code (e.g. UK ) I would like to set a property in the instances, hope this makes sense.
>>
>>Closest you can get is probably something like:

foreach(Info i in list.Where(x=>x.Postcode.StartsWith="HR"))
>>            {
>>                i.SomeProperty = true;
>>            }

>
>List does have a foreach method (http://msdn.microsoft.com/en-us/library/bwabdf9z%28v=vs.110%29.aspx), but its not really recommended (http://blogs.msdn.com/b/ericlippert/archive/2009/05/18/foreach-vs-foreach.aspx). There is also a parallel foreach (http://msdn.microsoft.com/en-us/library/dd992001%28v=vs.110%29.aspx) you could use if setting the value has no side effects.

Not sure I agree with the arguments against .ForEach. Anyway, interesting that Reflector for ForEach shows::

public void ForEach(Action<T> action)
{
    if (action == null)
    {
        ThrowHelper.ThrowArgumentNullException(ExceptionArgument.match);
    }
    for (int i = 0; i < this._size; i++)
    {
        action(this._items[i]);
    }
}

and foreach:

public bool MoveNext()
{
    if (this.version != this.list._version)
    {
        ThrowHelper.ThrowInvalidOperationException(ExceptionResource.InvalidOperation_EnumFailedVersion);
    }
    if (this.index < this.list._size)
    {
        this.current = this.list._items[this.index];
        this.index++;
        return true;
    }
    this.index = this.list._size + 1;
    this.current = default(T);
    return false;
}