Zend Zend Certifications 200-550 Questions & Answers

• Question 131:

  Which of the following is NOT true about PHP traits? (Choose 2)

  A. Multiple traits can be used by a single class.

  B. A trait can implement an interface.

  C. A trait can declare a private variable.

  D. Traits are able to be auto-loaded.

  E. Traits automatically resolve conflicts based on definition order.

  Correct Answer: BE

• Question 132:

  Given the following code, what will the output be:

  trait MyTrait {

  private $abc = 1;

  public function increment() {

  $this->abc++;

  }

  public function getValue() {

  return $this->abc;

  }

  }

  class MyClass {

  use MyTrait;

  public function incrementBy2() {

  $this->increment();

  $this->abc++;

  }

  }

  $c = new MyClass;

  $c->incrementBy2();

  var_dump($c->getValue());

  A. Fatal error: Access to private variable MyTrait::$abc from context MyClass

  B. Notice: Undefined property MyClass::$abc

  C. int(2)

  D. int(3)

  E. NULL

  Correct Answer: D

• Question 133:

  What is the output of the following code? var_dump(boolval([]));

  A. bool(true)

  B. bool(false)

  Correct Answer: B

• Question 134:

  What is the output of the following code? var_dump(boolval(new StdClass()));

  A. bool(true)

  B. bool(false)

  Correct Answer: A

• Question 135:

  Which php.ini setting is usually required to use an opcode cache?

  A. extension

  B. zend_extension

  C. optimizer

  D. dl

  Correct Answer: B

• Question 136:

  What is the output of the following code? var_dump(boolval(-1));

  A. bool(true)

  B. bool(false)

  Correct Answer: A

• Question 137:

  What will an opcode cache ALWAYS automatically improve?

  A. Running time of a loop in a PHP script

  B. Efficiency of HTML markup generated by a PHP script

  C. Execution speed of a PHP script

  D. Memory footprint of a PHP script

  E. None of the above

  Correct Answer: E

• Question 138:

  What is cached by an opcode cache?

  A. Compiled PHP code

  B. Native PHP extensions

  C. Data sent to the client

  D. Data received from the database

  Correct Answer: A

• Question 139:

  What function can be used to retrieve an array of current options for a stream context?

  A. stream_context_get_params

  B. stream_context_get_default

  C. stream_context_get_options

  D. The 'options' element of the stream_get_meta_data return value

  Correct Answer: C

• Question 140:

  When retrieving data from URLs, what are valid ways to make sure all file_get_contents calls send a certain user agent string? (Choose 2)

  A. $default_opts = array('http'=>array('user_agent'=>"My Cool Browser"));$default = stream_context_set_default($default_opts);

  B. stream_context_set_option("user_agent", "My Cool Browser");

  C. ini_set('user_agent', "My Cool Browser");

  D. stream_context_set_option($context, "http", "user_agent", "My Cool Browser");

  Correct Answer: AC