Yii check if homepage

If You want to check the current page, ie action is the default of the current controller..

$controller = Yii::app()->getController();
$isHome = $controller->action->id === $controller->defaultAction->id ? true : false;

dafeultaction may not always be 'index', it can be changed, so you need to compare it with defaultAction instead..

And by homepage if you mean the defult page of site, then you need to compare your controller also with defaultController..

$controller = Yii::app()->getController();
$default_controller = Yii::app()->defaultController;
$isHome = (($controller->id === $default_controller->id) && ($controller->action->id === $controller->defaultAction->id)) ? true : false;

In Yii2:

$controller = Yii::$app->controller;
$default_controller = Yii::$app->defaultRoute;
$isHome = (($controller->id === $default_controller) && ($controller->action->id === $controller->defaultAction)) ? true : false;

This is what I use to check if I'm on the frontpage:

$isFrontpage = false;
if ((Yii::app()->controller->getId().'/'.Yii::app()->controller->getAction()->getId()) == 'site/index'  ) { 
    $isFrontpage = true;
}

Works like a charm.... even on views...

May be this help you:)

<?php
  $controllerl = Yii::$app->controller;
  $homecheker = $controllerl->id.'/'.$controllerl->action->id;
  if($homecheker=='site/index')
  {
     //no border on home page
     $mymaincls ='main-nav navbar-fixed-top';
  }else
  {
     //border all other page
     $mymaincls ='main-nav navbar-fixed-top header-border';
  }
?>