I have a method for sorting generic lists by the object fields:

public static IQueryable<T> SortTable<T>(IQueryable<T> q, string sortfield, bool ascending)
{
    var p = Expression.Parameter(typeof(T), "p");

    if (typeof(T).GetProperty(sortfield).PropertyType == typeof(int?))
    {
        var x = Expression.Lambda<Func<T, int?>>(Expression.Property(p, sortfield), p);
        if (ascending)
            q = q.OrderBy(x);
        else
            q = q.OrderByDescending(x);
    }
    else if (typeof(T).GetProperty(sortfield).PropertyType == typeof(int))
    {
        var x = Expression.Lambda<Func<T, int>>(Expression.Property(p, sortfield), p);
        if (ascending)
            q = q.OrderBy(x);
        else
            q = q.OrderByDescending(x);
    }
    else if (typeof(T).GetProperty(sortfield).PropertyType == typeof(DateTime))
    {
        var x = Expression.Lambda<Func<T, DateTime>>(Expression.Property(p, sortfield), p);
        if (ascending)
            q = q.OrderBy(x);
        else
            q = q.OrderByDescending(x);
    }
    // many more for every type
    return q;
}

Is there any way I can collapse those ifs to a single generic statement? The main problem is that for the part Expression.Lambda<Func<T, int>> I am not sure how to write it generically.