Basics

Question 1

What is PHP?

Answer 1

It is an open-source general-purpose scripting language.
it’s server-side.
Best suited for web development.
It’s an interpreted language.

Question 2

Why you should learn PHP?

Answer 2

1. Multi-purpose: good for simple and complex websites.
2. CRM portals
3. e-commerce systems
4. Rest Api
5. image/audio processing
6. works with almost all data bases

Question 3

PHP CMS?

Answer 3

wordpress, Magento, Drupal, OpenCart

Question 4

For what is not great php?

Answer 4

For building real time apps(better Nodejs)
For AI and ML (better Python)

Question 5

How do you comment in PHP?

Answer 5

// single line
# single line
/* multi line */

Question 6

Do variables have types in PHP?

Answer 6

No, PHP is loosely typed.

Question 7

How do you declare a variable?

Answer 7

with $

$my_name=’victoria’

Question 8

What types are there in PHP?

Answer 8

1. Strings
2. Integer
3. Float/Double
4. Boolean
5. Null
6. Array
7. Object
8. Resource

Question 9

How do you print a variable?

Answer 9

With echo

echo $variable

Question 10

How do you concatenate in php?

Answer 10

with .

echo $name.’ ‘.$lastname

Question 11

What happens if you try to print a boolean?

Answer 11

It converts it to a string : 1 for true and empty for false.

Question 12

What happens if you try to print null?

Answer 12

It prints an empty string

Question 13

How do you see the type of a variable?

Answer 13

with gettype($name);

Question 14

How do I print a variable to see its type, length and value?

Answer 14

with var_dump()

var_dump($name) => string(4)”vica”

puedo pasarle más de una variable

Question 15

Which ones are the variable type checking functions to see if a variable is a boolean, or a string, etc?

Answer 15

is_string($my_var)

is_int($my_var) / is_integer($my_var)

is_float($my_var) / is_double($my_var)

is_numeric($my_var)

is_bool($my_var)

Question 16

How do you check if a variable exists?

Answer 16

With isset()

isset($name)

esto devuelve un boolean

Question 17

How do you create a constant?

Answer 17

with define()

define(‘PI’,3.14)

Se pone primero el nombre, y después el valor.