diff --git a/framework/yii/base/Formatter.php b/framework/yii/base/Formatter.php
index 545f570..b3457de 100644
--- a/framework/yii/base/Formatter.php
+++ b/framework/yii/base/Formatter.php
@@ -37,6 +37,10 @@ class Formatter extends Component
 	 */
 	public $datetimeFormat = 'Y/m/d h:i:s A';
 	/**
+	 * @var string the text to be displayed when formatting a null. Defaults to '(not set)'.
+	 */
+	public $nullDisplay;
+	/**
 	 * @var array the text to be displayed when formatting a boolean value. The first element corresponds
 	 * to the text display for false, the second element for true. Defaults to `array('No', 'Yes')`.
 	 */
@@ -61,6 +65,9 @@ class Formatter extends Component
 		if (empty($this->booleanFormat)) {
 			$this->booleanFormat = array(Yii::t('yii', 'No'), Yii::t('yii', 'Yes'));
 		}
+		if ($this->nullDisplay === null) {
+			$this->nullDisplay = Yii::t('yii', '(not set)');
+		}
 	}
 
 	/**
@@ -71,6 +78,9 @@ class Formatter extends Component
 	 */
 	public function asRaw($value)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return $value;
 	}
 
@@ -81,6 +91,9 @@ class Formatter extends Component
 	 */
 	public function asText($value)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return Html::encode($value);
 	}
 
@@ -91,6 +104,9 @@ class Formatter extends Component
 	 */
 	public function asNtext($value)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return nl2br(Html::encode($value));
 	}
 
@@ -103,6 +119,9 @@ class Formatter extends Component
 	 */
 	public function asParagraphs($value)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return str_replace('<p></p>', '',
 			'<p>' . preg_replace('/[\r\n]{2,}/', "</p>\n<p>", Html::encode($value)) . '</p>'
 		);
@@ -118,6 +137,9 @@ class Formatter extends Component
 	 */
 	public function asHtml($value, $config = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return HtmlPurifier::process($value, $config);
 	}
 
@@ -128,6 +150,9 @@ class Formatter extends Component
 	 */
 	public function asEmail($value)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return Html::mailto($value);
 	}
 
@@ -138,6 +163,9 @@ class Formatter extends Component
 	 */
 	public function asImage($value)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return Html::img($value);
 	}
 
@@ -148,6 +176,9 @@ class Formatter extends Component
 	 */
 	public function asUrl($value)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		$url = $value;
 		if (strpos($url, 'http://') !== 0 && strpos($url, 'https://') !== 0) {
 			$url = 'http://' . $url;
@@ -163,6 +194,9 @@ class Formatter extends Component
 	 */
 	public function asBoolean($value)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return $value ? $this->booleanFormat[1] : $this->booleanFormat[0];
 	}
 
@@ -183,6 +217,9 @@ class Formatter extends Component
 	 */
 	public function asDate($value, $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		$value = $this->normalizeDatetimeValue($value);
 		return date($format === null ? $this->dateFormat : $format, $value);
 	}
@@ -204,6 +241,9 @@ class Formatter extends Component
 	 */
 	public function asTime($value, $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		$value = $this->normalizeDatetimeValue($value);
 		return date($format === null ? $this->timeFormat : $format, $value);
 	}
@@ -225,6 +265,9 @@ class Formatter extends Component
 	 */
 	public function asDatetime($value, $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		$value = $this->normalizeDatetimeValue($value);
 		return date($format === null ? $this->datetimeFormat : $format, $value);
 	}
@@ -256,6 +299,9 @@ class Formatter extends Component
 	 */
 	public function asInteger($value)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		if (is_string($value) && preg_match('/^(-?\d+)/', $value, $matches)) {
 			return $matches[1];
 		} else {
@@ -274,6 +320,9 @@ class Formatter extends Component
 	 */
 	public function asDouble($value, $decimals = 2)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		if ($this->decimalSeparator === null) {
 			return sprintf("%.{$decimals}f", $value);
 		} else {
@@ -292,6 +341,9 @@ class Formatter extends Component
 	 */
 	public function asNumber($value, $decimals = 0)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		$ds = isset($this->decimalSeparator) ? $this->decimalSeparator: '.';
 		$ts = isset($this->thousandSeparator) ? $this->thousandSeparator: ',';
 		return number_format($value, $decimals, $ds, $ts);
diff --git a/framework/yii/i18n/Formatter.php b/framework/yii/i18n/Formatter.php
index 948e277..979a46f 100644
--- a/framework/yii/i18n/Formatter.php
+++ b/framework/yii/i18n/Formatter.php
@@ -120,6 +120,9 @@ class Formatter extends \yii\base\Formatter
 	 */
 	public function asDate($value, $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		$value = $this->normalizeDatetimeValue($value);
 		if ($format === null) {
 			$format = $this->dateFormat;
@@ -153,6 +156,9 @@ class Formatter extends \yii\base\Formatter
 	 */
 	public function asTime($value, $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		$value = $this->normalizeDatetimeValue($value);
 		if ($format === null) {
 			$format = $this->timeFormat;
@@ -186,6 +192,9 @@ class Formatter extends \yii\base\Formatter
 	 */
 	public function asDatetime($value, $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		$value = $this->normalizeDatetimeValue($value);
 		if ($format === null) {
 			$format = $this->datetimeFormat;
@@ -208,6 +217,9 @@ class Formatter extends \yii\base\Formatter
 	 */
 	public function asDecimal($value, $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return $this->createNumberFormatter(NumberFormatter::DECIMAL, $format)->format($value);
 	}
 
@@ -221,6 +233,9 @@ class Formatter extends \yii\base\Formatter
 	 */
 	public function asCurrency($value, $currency = 'USD', $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return $this->createNumberFormatter(NumberFormatter::CURRENCY, $format)->formatCurrency($value, $currency);
 	}
 
@@ -233,6 +248,9 @@ class Formatter extends \yii\base\Formatter
 	 */
 	public function asPercent($value, $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return $this->createNumberFormatter(NumberFormatter::PERCENT, $format)->format($value);
 	}
 
@@ -245,6 +263,9 @@ class Formatter extends \yii\base\Formatter
 	 */
 	public function asScientific($value, $format = null)
 	{
+		if ($value === null) {
+			return $this->nullDisplay;
+		}
 		return $this->createNumberFormatter(NumberFormatter::SCIENTIFIC, $format)->format($value);
 	}
 
diff --git a/tests/unit/framework/base/FormatterTest.php b/tests/unit/framework/base/FormatterTest.php
index 87a41c9..b851ae1 100644
--- a/tests/unit/framework/base/FormatterTest.php
+++ b/tests/unit/framework/base/FormatterTest.php
@@ -42,6 +42,7 @@ class FormatterTest extends TestCase
 		$this->assertSame($value, $this->formatter->asRaw($value));
 		$value = '<>';
 		$this->assertSame($value, $this->formatter->asRaw($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asRaw(null));
 	}
 
 	public function testAsText()
@@ -52,6 +53,7 @@ class FormatterTest extends TestCase
 		$this->assertSame("$value", $this->formatter->asText($value));
 		$value = '<>';
 		$this->assertSame('&lt;&gt;', $this->formatter->asText($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asText(null));
 	}
 
 	public function testAsNtext()
@@ -64,6 +66,7 @@ class FormatterTest extends TestCase
 		$this->assertSame('&lt;&gt;', $this->formatter->asNtext($value));
 		$value = "123\n456";
 		$this->assertSame("123<br />\n456", $this->formatter->asNtext($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asNtext(null));
 	}
 
 	public function testAsParagraphs()
@@ -80,6 +83,7 @@ class FormatterTest extends TestCase
 		$this->assertSame("<p>123</p>\n<p>456</p>", $this->formatter->asParagraphs($value));
 		$value = "123\n\n\n456";
 		$this->assertSame("<p>123</p>\n<p>456</p>", $this->formatter->asParagraphs($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asParagraphs(null));
 	}
 
 	public function testAsHtml()
@@ -91,12 +95,14 @@ class FormatterTest extends TestCase
 	{
 		$value = 'test@sample.com';
 		$this->assertSame("<a href=\"mailto:$value\">$value</a>", $this->formatter->asEmail($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asEmail(null));
 	}
 
 	public function testAsImage()
 	{
 		$value = 'http://sample.com/img.jpg';
 		$this->assertSame("<img src=\"$value\" alt=\"\">", $this->formatter->asImage($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asImage(null));
 	}
 
 	public function testAsBoolean()
@@ -109,6 +115,7 @@ class FormatterTest extends TestCase
 		$this->assertSame('Yes', $this->formatter->asBoolean($value));
 		$value = "";
 		$this->assertSame('No', $this->formatter->asBoolean($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asBoolean(null));
 	}
 
 	public function testAsDate()
@@ -116,6 +123,7 @@ class FormatterTest extends TestCase
 		$value = time();
 		$this->assertSame(date('Y/m/d', $value), $this->formatter->asDate($value));
 		$this->assertSame(date('Y-m-d', $value), $this->formatter->asDate($value, 'Y-m-d'));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asDate(null));
 	}
 
 	public function testAsTime()
@@ -123,6 +131,7 @@ class FormatterTest extends TestCase
 		$value = time();
 		$this->assertSame(date('h:i:s A', $value), $this->formatter->asTime($value));
 		$this->assertSame(date('h:i:s', $value), $this->formatter->asTime($value, 'h:i:s'));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asTime(null));
 	}
 
 	public function testAsDatetime()
@@ -130,6 +139,7 @@ class FormatterTest extends TestCase
 		$value = time();
 		$this->assertSame(date('Y/m/d h:i:s A', $value), $this->formatter->asDatetime($value));
 		$this->assertSame(date('Y-m-d h:i:s', $value), $this->formatter->asDatetime($value, 'Y-m-d h:i:s'));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asDatetime(null));
 	}
 
 	public function testAsInteger()
@@ -144,6 +154,7 @@ class FormatterTest extends TestCase
 		$this->assertSame("-123", $this->formatter->asInteger($value));
 		$value = "-123abc";
 		$this->assertSame("-123", $this->formatter->asInteger($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asInteger(null));
 	}
 
 	public function testAsDouble()
@@ -161,6 +172,7 @@ class FormatterTest extends TestCase
 		$this->assertSame("123", $this->formatter->asDouble($value, 0));
 		$value = 123123.123;
 		$this->assertSame("123123,12", $this->formatter->asDouble($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asDouble(null));
 	}
 
 	public function testAsNumber()
@@ -175,5 +187,6 @@ class FormatterTest extends TestCase
 		$this->formatter->thousandSeparator = '';
 		$this->assertSame("123123", $this->formatter->asNumber($value));
 		$this->assertSame("123123,12", $this->formatter->asNumber($value, 2));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asNumber(null));
 	}
 }
diff --git a/tests/unit/framework/i18n/FormatterTest.php b/tests/unit/framework/i18n/FormatterTest.php
index 2a67422..c13fff3 100644
--- a/tests/unit/framework/i18n/FormatterTest.php
+++ b/tests/unit/framework/i18n/FormatterTest.php
@@ -47,6 +47,7 @@ class FormatterTest extends TestCase
 		$this->assertSame("123,456", $this->formatter->asDecimal($value));
 		$value = '-123456.123';
 		$this->assertSame("-123,456.123", $this->formatter->asDecimal($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asDecimal(null));
 	}
 
 	public function testAsPercent()
@@ -57,6 +58,7 @@ class FormatterTest extends TestCase
 		$this->assertSame("12%", $this->formatter->asPercent($value));
 		$value = '-0.009343';
 		$this->assertSame("-1%", $this->formatter->asPercent($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asPercent(null));
 	}
 
 	public function testAsScientific()
@@ -67,6 +69,7 @@ class FormatterTest extends TestCase
 		$this->assertSame("1.23456E5", $this->formatter->asScientific($value));
 		$value = '-123456.123';
 		$this->assertSame("-1.23456123E5", $this->formatter->asScientific($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asScientific(null));
 	}
 
 	public function testAsCurrency()
@@ -77,6 +80,7 @@ class FormatterTest extends TestCase
 		$this->assertSame("$123.46", $this->formatter->asCurrency($value));
 		$value = '-123456.123';
 		$this->assertSame("($123,456.12)", $this->formatter->asCurrency($value));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asCurrency(null));
 	}
 
 	public function testDate()
@@ -84,5 +88,6 @@ class FormatterTest extends TestCase
 		$time = time();
 		$this->assertSame(date('n/j/y', $time), $this->formatter->asDate($time));
 		$this->assertSame(date('F j, Y', $time), $this->formatter->asDate($time, 'long'));
+		$this->assertSame($this->formatter->nullDisplay, $this->formatter->asDate(null));
 	}
 }