How to extend MVC3 Label and LabelFor HTML helpers?

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You can easily extend the label by creating your own LabelFor:

Something like this should do what you need

public static MvcHtmlString LabelFor<TModel, TValue>(this HtmlHelper<TModel> html, Expression<Func<TModel, TValue>> expression, object htmlAttributes)
{
  return LabelFor(html, expression, new RouteValueDictionary(htmlAttributes));
}

public static MvcHtmlString LabelFor<TModel, TValue>(this HtmlHelper<TModel> html, Expression<Func<TModel, TValue>> expression, IDictionary<string, object> htmlAttributes)
{
  ModelMetadata metadata = ModelMetadata.FromLambdaExpression(expression, html.ViewData);
  string htmlFieldName = ExpressionHelper.GetExpressionText(expression);
  string labelText = metadata.DisplayName ?? metadata.PropertyName ?? htmlFieldName.Split('.').Last();
  if (String.IsNullOrEmpty(labelText))
  {
    return MvcHtmlString.Empty;
  }

  TagBuilder tag = new TagBuilder("label");
  tag.MergeAttributes(htmlAttributes);
  tag.Attributes.Add("for", html.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldId(htmlFieldName));
  tag.SetInnerText(labelText);
  return MvcHtmlString.Create(tag.ToString(TagRenderMode.Normal));
}

Update
To use the extension method just created in your project, add this line in your Views\web.config

<pages>
  <namespaces>
    <add namespace="System.Web.Helpers" />
    <add namespace="System.Web.Mvc" />
    <add namespace="System.Web.Mvc.Ajax" />
    <add namespace="System.Web.Mvc.Html" />
    <add namespace="System.Web.Routing" />
    <add namespace="System.Web.WebPages" />
    <add namespace="MyProject.Helpers" />   <-- my extension

    ...

 </namespaces>
</pages>

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