# Class yii\web\ErrorHandler

Inheritance | yii\web\ErrorHandler » yii\base\ErrorHandler » yii\base\Component » yii\base\BaseObject
Implements | yii\base\Configurable
Available since version | 2.0
Source Code | https://github.com/yiisoft/yii2/blob/master/framework/web/ErrorHandler.php

ErrorHandler handles uncaught PHP errors and exceptions.

ErrorHandler displays these errors using appropriate views based on the nature of the errors and the mode the application runs at.

ErrorHandler is configured as an application component in yii\base\Application by default. You can access that instance via `Yii::$app->errorHandler`.

For more details and usage information on ErrorHandler, see the guide article on handling errors.

## Public Properties

Hide inherited properties

Property | Type | Description | Defined By
--- | --- | --- | ---
$behaviors | yii\base\Behavior[] | List of behaviors attached to this component. This property is read-only. | yii\base\Component
$callStackItemView | string | The path of the view file for rendering exceptions and errors call stack element. | yii\web\ErrorHandler
$discardExistingOutput | boolean | Whether to discard any existing page output before error display. | yii\base\ErrorHandler
$displayVars | array | List of the PHP predefined variables that should be displayed on the error page. | yii\web\ErrorHandler
$errorAction | string | The route (e.g. `site/error`) to the controller action that will be used to display external errors. | yii\web\ErrorHandler
$errorView | string | The path of the view file for rendering exceptions without call stack information. | yii\web\ErrorHandler
$exception | Exception|null | The exception that is being handled currently. | yii\base\ErrorHandler
$exceptionView | string | The path of the view file for rendering exceptions. | yii\web\ErrorHandler
$maxSourceLines | integer | Maximum number of source code lines to be displayed. | yii\web\ErrorHandler
$maxTraceSourceLines | integer | Maximum number of trace source code lines to be displayed. | yii\web\ErrorHandler
$memoryReserveSize | integer | The size of the reserved memory. | yii\base\ErrorHandler
$previousExceptionView | string | The path of the view file for rendering previous exceptions. | yii\web\ErrorHandler
$silentExitOnException | boolean | If true - `handleException()` will finish script with `ExitCode::OK`. | yii\base\ErrorHandler
$traceLine | string | Trace line with placeholders to be be substituted. | yii\web\ErrorHandler

## Public Methods

Hide inherited methods

Method | Description | Defined By
--- | --- | ---
__call() | Calls the named method which is not a class method. | yii\base\Component
__clone() | This method is called after the object is created by cloning an existing one. | yii\base\Component
__construct() | Constructor. | yii\base\BaseObject
__get() | Returns the value of a component property. | yii\base\Component
__isset() | Checks if a property is set, i.e. defined and not null. | yii\base\Component
__set() | Sets the value of a component property. | yii\base\Component
__unset() | Sets a component property to be null. | yii\base\Component
addTypeLinks() | Adds informational links to the given PHP type/class. | yii\web\ErrorHandler
argumentsToString() | Converts arguments array to its string representation. | yii\web\ErrorHandler
attachBehavior() | Attaches a behavior to this component. | yii\base\Component
attachBehaviors() | Attaches a list of behaviors to the component. | yii\base\Component
behaviors() | Returns a list of behaviors that this component should behave as. | yii\base\Component
canGetProperty() | Returns a value indicating whether a property can be read. | yii\base\Component
canSetProperty() | Returns a value indicating whether a property can be set. | yii\base\Component
className() | Returns the fully qualified name of this class. | yii\base\BaseObject
clearOutput() | Removes all output echoed before calling this method. | yii\base\ErrorHandler
convertExceptionToError() | Converts an exception into a PHP error. | yii\base\ErrorHandler
convertExceptionToString() | Converts an exception into a simple string. | yii\base\ErrorHandler
convertExceptionToVerboseString() | Converts an exception into a string that has verbose information about the exception and its trace. | yii\base\ErrorHandler
createFrameworkVersionLink() | Creates string containing HTML link which refers to the page with the current version of the framework and version number text. | yii\web\ErrorHandler
createHttpStatusLink() | Creates HTML containing link to the page with the information on given HTTP status code. | yii\web\ErrorHandler
createServerInformationLink() | Creates string containing HTML link which refers to the home page of determined web-server software and its full name. | yii\web\ErrorHandler
detachBehavior() | Detaches a behavior from the component. | yii\base\Component
detachBehaviors() | Detaches all behaviors from the component. | yii\base\Component
ensureBehaviors() | Makes sure that the behaviors declared in behaviors() are attached to this component. | yii\base\Component
getBehavior() | Returns the named behavior object. | yii\base\Component
getBehaviors() | Returns all behaviors attached to this component. | yii\base\Component
getExceptionName() | Returns human-readable exception name. | yii\web\ErrorHandler
handleError() | Handles PHP execution errors such as warnings and notices. | yii\base\ErrorHandler
handleException() | Handles uncaught PHP exceptions. | yii\base\ErrorHandler
handleFatalError() | Handles fatal PHP errors. | yii\base\ErrorHandler
handleHhvmError() | Handles HHVM execution errors such as warnings and notices. | yii\base\ErrorHandler
hasEventHandlers() | Returns a value indicating whether there is any handler attached to the named event. | yii\base\Component
hasMethod() | Returns a value indicating whether a method is defined. | yii\base\Component
hasProperty() | Returns a value indicating whether a property is defined for this component. | yii\base\Component
htmlEncode() | Converts special characters to HTML entities. | yii\web\ErrorHandler
init() |  | yii\base\ErrorHandler
isCoreFile() | Determines whether given name of the file belongs to the framework. | yii\web\ErrorHandler
logException() | Logs the given exception. | yii\base\ErrorHandler
off() | Detaches an existing event handler from this component. | yii\base\Component
on() | Attaches an event handler to an event. | yii\base\Component
register() | Register this error handler. | yii\base\ErrorHandler
renderCallStack() | Renders call stack. | yii\web\ErrorHandler
renderCallStackItem() | Renders a single call stack element. | yii\web\ErrorHandler
renderFile() | Renders a view file as a PHP script. | yii\web\ErrorHandler
renderPreviousExceptions() | Renders the previous exception stack for a given Exception. | yii\web\ErrorHandler
renderRequest() | Renders the global variables of the request. | yii\web\ErrorHandler
trigger() | Triggers an event. | yii\base\Component
unregister() | Unregisters this error handler by restoring the PHP error and exception handlers. | yii\base\ErrorHandler

## Protected Methods

Hide inherited methods

Method | Description | Defined By
--- | --- | ---
convertExceptionToArray() | Converts an exception into an array. | yii\web\ErrorHandler
getTypeUrl() | Returns the informational link URL for a given PHP type/class. | yii\web\ErrorHandler
handleFallbackExceptionMessage() | Handles exception thrown during exception processing in handleException(). | yii\base\ErrorHandler
renderException() | Renders the exception. | yii\web\ErrorHandler
shouldRenderSimpleHtml() |  | yii\web\ErrorHandler

## Property Details

$callStackItemView public property

The path of the view file for rendering exceptions and errors call stack element.

public string $callStackItemView = '@yii/views/errorHandler/callStackItem.php'
$displayVars public property (available since version 2.0.7)

List of the PHP predefined variables that should be displayed on the error page. Note that a variable must be accessible via `$GLOBALS`. Otherwise it won't be displayed. Defaults to `['_GET', '_POST', '_FILES', '_COOKIE', '_SESSION']`.

See also renderRequest().

public array $displayVars = ['_GET', '_POST', '_FILES', '_COOKIE', '_SESSION']
$errorAction public property

The route (e.g. `site/error`) to the controller action that will be used to display external errors. Inside the action, it can retrieve the error information using `Yii::$app->errorHandler->exception`. This property defaults to null, meaning ErrorHandler will handle the error display.

public string $errorAction = null
$errorView public property

The path of the view file for rendering exceptions without call stack information.

public string $errorView = '@yii/views/errorHandler/error.php'
$exceptionView public property

The path of the view file for rendering exceptions.

public string $exceptionView = '@yii/views/errorHandler/exception.php'
$maxSourceLines public property

Maximum number of source code lines to be displayed. Defaults to 19.

public integer $maxSourceLines = 19
$maxTraceSourceLines public property

Maximum number of trace source code lines to be displayed. Defaults to 13.

public integer $maxTraceSourceLines = 13
$previousExceptionView public property

The path of the view file for rendering previous exceptions.

public string $previousExceptionView = '@yii/views/errorHandler/previousException.php'
$traceLine public property (available since version 2.0.14)

Trace line with placeholders to be be substituted. The placeholders are {file}, {line} and {text} and the string should be as follows.

`File: {file} - Line: {line} - Text: {text}`

See also https://github.com/yiisoft/yii2-debug#open-files-in-ide.

public string $traceLine = '{html}'

## Method Details

addTypeLinks() public method

Adds informational links to the given PHP type/class.

public string addTypeLinks ( $code )
$code | string | Type/class name to be linkified.
return | string | Linkified with HTML type/class name.

argumentsToString() public method

Converts arguments array to its string representation.

public string argumentsToString ( $args )
$args | array | Arguments array to be converted
return | string | String representation of the arguments array

convertExceptionToArray() protected method

Converts an exception into an array.

protected array convertExceptionToArray ( $exception )
$exception | Exception|Error | The exception being converted
return | array | The array representation of the exception.

createFrameworkVersionLink() public method

Creates string containing HTML link which refers to the page with the current version of the framework and version number text.

public string createFrameworkVersionLink ( )
return | string | Framework version information hyperlink.

createHttpStatusLink() public method

Creates HTML containing link to the page with the information on given HTTP status code.

public string createHttpStatusLink ( $statusCode, $statusDescription )
$statusCode | integer | To be used to generate information link.
$statusDescription | string | Description to display after the the status code.
return | string | Generated HTML with HTTP status code information.

createServerInformationLink() public method

Creates string containing HTML link which refers to the home page of determined web-server software and its full name.

public string createServerInformationLink ( )
return | string | Server software information hyperlink.

getExceptionName() public method

Returns human-readable exception name.

public string|null getExceptionName ( $exception )
$exception | Exception |
return | string|null | Human-readable exception name or null if it cannot be determined

getTypeUrl() protected method

Returns the informational link URL for a given PHP type/class.

See also addTypeLinks().

protected string|null getTypeUrl ( $class, $method )
$class | string | The type or class name.
$method | string|null | The method name.
return | string|null | The informational link URL.

htmlEncode() public method

Converts special characters to HTML entities.

public string htmlEncode ( $text )
$text | string | To encode.
return | string | Encoded original text.

isCoreFile() public method

Determines whether given name of the file belongs to the framework.

public boolean isCoreFile ( $file )
$file | string | Name to be checked.
return | boolean | Whether given name of the file belongs to the framework.

renderCallStack() public method (available since version 2.0.12)

Renders call stack.

public string renderCallStack ( $exception )
$exception | Exception|ParseError | Exception to get call stack from
return | string | HTML content of the rendered call stack.

renderCallStackItem() public method

Renders a single call stack element.

public string renderCallStackItem ( $file, $line, $class, $method, $args, $index )
$file | string|null | Name where call has happened.
$line | integer|null | Number on which call has happened.
$class | string|null | Called class name.
$method | string|null | Called function/method name.
$args | array | Array of method arguments.
$index | integer | Number of the call stack element.
return | string | HTML content of the rendered call stack element.

renderException() protected method

Renders the exception.

protected void renderException ( $exception )
$exception | Exception|Error | The exception to be rendered.

renderFile() public method

Renders a view file as a PHP script.

public string renderFile ( $_file_, $_params_ )
$_file_ | string | The view file.
$_params_ | array | The parameters (name-value pairs) that will be extracted and made available in the view file.
return | string | The rendering result

renderPreviousExceptions() public method

Renders the previous exception stack for a given Exception.

public string renderPreviousExceptions ( $exception )
$exception | Exception | The exception whose precursors should be rendered.
return | string | HTML content of the rendered previous exceptions. Empty string if there are none.

renderRequest() public method

Renders the global variables of the request.

List of global variables is defined in $displayVars.

See also $displayVars.

public string renderRequest ( )
return | string | The rendering result

shouldRenderSimpleHtml() protected method (available since version 2.0.12)

protected boolean shouldRenderSimpleHtml ( )
return | boolean | If simple HTML should be rendered