IntroductionTypeError class extends Error class. This error is raised when actual and formal argument types don't match, return type doesn't match the decalred returned type or invalid arguments passed to any built-in functionNote that strict_types should be set to true with declare() function at the top of script −In this example, types of formal and actual argument variables don't match, resulting in TypeError.Example Live DemoThis will produce following result −OutputArgument 1 passed to add() must be of the type integer, string given, called in C:\xampp\php\test.php on line 9In following example, user defined function is supposed to return integer data, instead it is returning ... Read More

IntroductionPHP's internal Error types are represented by classes that are inherited from Error class. The Error class implements Throwable interface. Properties and methods of Error class are as follows −propertiesmessage − The error messagecode − The error codefile − The filename where the error happenedline − The line where the error happenedmethods__construct() − Construct the error objectgetMessage() − Gets the error messagegetPrevious() − Returns previous ThrowablegetCode() − Gets the error codegetFile() − Gets the file in which the error occurredgetLine() − Gets the line in which the error occurredgetTrace() − Gets the stack tracegetTraceAsString() − Gets the stack trace as ... Read More

IntroductionPHP's ZIP extension registers zip:// wrapper. PHP 7.2.0 onwards supports passwords for encrypted archives. There is only one Zip context option called passwordExampleFirst create ZIP archive as follows:

IntroductionList of Context options for ssl:// and tls:// transports.peer_namePeer name to be used. If this value is not set, then the name is guessed based on the hostname used when opening the stream.verify_peerRequire verification of SSL certificate used. Defaults to TRUE.verify_peer_nameRequire verification of peer name. Defaults to TRUE.allow_self_signedAllow self-signed certificates. Requires verify_peer. Defaults to FALSEcafileLocation of Certificate Authority file on local filesystem to be used to authenticate identity of remote peer.capathmust be a correctly hashed certificate directory.local_certPath to local certificate file on filesystem.local_pkPath to local private key file on filesystem in case of separate files for certificate and private key.passphrasePassphrase with which ... Read More

IntroductionAccess to filesystem and various other stream wrappers can be customized by various context options and parameters configures by stream_context_create() and stream_context_set_option() functions.Following list shows various socket context options are available for all wrappers that work over sockets, like tcp, http and ftp.bindtospecifies the IP address (either IPv4 or IPv6) and/or the port number used to access the network. (ip:port for IPv4 [ip]:port for IPv6).backloglimits number of outstanding connections in socket's listen queue.ipv6_v6onlyOverrides the OS default regarding mapping IPv4 into IPv6.so_reuseportAllows multiple bindings to a same ip:port pair.so_broadcastEnables sending and receiving data to/from broadcast addresses.tcp_nodelayIf TRUE, sets SOL_TCP, NO_DELAY=1 appropriately, disabling ... Read More

IntroductionPhar stands for PHP Archive. All the resources of a certain PHP application or library are packages in a single .phar file for the purpose of istribution. A phar file can be used as IO stream with phar:// wrapper. Context options for phar:// wrapper are listed as follows −compressPHP has following predefined constants for defining compression formatsConstantValueDescriptionPhar::NONE0x00000000no compressionPhar::COMPRESSED0x0000F000bitmask with file flags to determine if any compression is presenPhar::GZ0x00001000zlib (gzip) compressionPhar::BZ20x00002000bzip2 compressionmetadataAny PHP variable containing information to store that describes the phar archive is used as argument for Phar::setMetadata() methodExampleThis example Phar context option set for creating Phar fileRead More

IntroductionContext parameters allow customization of access to filesystem and other stream wrappers. To configure a stream, PHP has stream_context_set_params() function.Syntaxstream_context_set_params ( resource $stream_or_context , array $params ) : bool$stream_or_context can be any of PHP's supported streams/wrappers/contexts$params is an array with following properties. should be an associative array of the structure − $params['paramname'] = "paramvalue";context parametersnotification − A user-defined callback to be called whenever a stream triggers a notification. Only for http:// and ftp:// stream wrappers.The notification callback function has following syntaxsyntaxstream_notification_callback ( int $notification_code , int $severity , string $message , int $message_code , int $bytes_transferred , int $bytes_max ) ... Read More

IntroductionPHP can interact with MongoDB database through database extensions. For older versions of PHP, mongo driver can be installed from PECL. This has now been replaced by mongodb driver. Both drivers can be installed using precompiled binaries for Linux/Windows/MacOS operating systems. Alternately, manual installation can be done from source tarball available on github. In either case, mongo or mongodb extension should be enabled in php.ini settings.The PHP MongoDB extension provides Stream Context Support using the mongodb context. Relevent context options are as followsOptionslog_cmd_insert ( array $server , array $document , array $writeOptions , array $protocolOptions )This is a callable function, used ... Read More

IntroductionGiven below is the list of context options for http:// and https:// transportsmethodHTTP method supported by the remote server. Defaults to GET.headerAdditional headers to be sent during request.user_agentValue to send with User-Agent: header. By default the user_agent php.ini setting is used.contentAdditional data to be sent after the headers. Typically used with POST or PUT requests.proxyURI specifying address of proxy server.request_fulluri booleanWhen set to TRUE, the entire URI will be used when constructing the request. Defaults to FALSE.follow_locationFollow Location header redirects. Set to 0 to disable.Defaults to 1.max_redirectsThe max number of redirects to follow.protocol_versionHTTP protocol version. Defaults to 1.0.timeoutRead timeout in seconds, ... Read More

IntroductionContext options for http:// and https:// transports are listed below −overwriteAllow overwriting of already existing files on remote server while uploading only.resume_posFile offset at which to begin transfer. Applies for downloading only.Defaults to 0 (Beginning of File).proxyProxy FTP request via http proxy server. Applies to file read operations only. Ex −tcp://squid.example.com:8000.This example shows how to allow fopen() to overwrite a file on an FTP site.Example