Get a text which specified with DisplayAttribute

GetDisplayName.cs

static string GetDisplayName<TModel>(Expression<Func<TModel, object>> expression)
{
    var type = typeof(TModel);
    var propertyList = default(IEnumerable<string>);

    switch (expression.Body.NodeType)
    {
        case ExpressionType.Convert:
        case ExpressionType.ConvertChecked:
            var ue = expression.Body as UnaryExpression;
            propertyList = (ue != null ? ue.Operand : null).ToString().Split(".".ToCharArray()).Skip(1);
            break;
        default:
            propertyList = expression.Body.ToString().Split(".".ToCharArray()).Skip(1);
            break;
    }

    var propertyName = propertyList.Last();
    var properties = propertyList.Take(propertyList.Count() - 1).ToArray();

    var expr = default(Expression);

    foreach (string property in properties)
    {
        var propertyInfo = type.GetProperty(property);

        expr = Expression.Property(expr, type.GetProperty(property));
        type = propertyInfo.PropertyType;
    }

    var attr = (DisplayAttribute)type.GetProperty(propertyName).GetCustomAttributes(typeof(DisplayAttribute), true).SingleOrDefault();

    if (attr == null)
    {
        MetadataTypeAttribute metadataType = (MetadataTypeAttribute)type.GetCustomAttributes(typeof(MetadataTypeAttribute), true).FirstOrDefault();
        if (metadataType != null)
        {
            var property = metadataType.MetadataClassType.GetProperty(propertyName);
            if (property != null)
            {
                attr = (DisplayAttribute)property.GetCustomAttributes(typeof(DisplayNameAttribute), true).SingleOrDefault();
            }
        }
    }

    return (attr != null) ? attr.Name : String.Empty;
}