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PHP Build a Simple PHP Application Listing Inventory Items Understanding Whitespace

Posted by Yaxin Yuan
Yaxin Yuan
11,191 Points

There is a line of code I do not quite understand, please help! 

echo '<img src="' . $product["img"] . '" alt="' . $product["name"] . '">';
  1. Why single quotation inside double quotation?
  2. Why concatenation?

Thank you!

2 Answers

Saad Lulu
Saad Lulu
6,821 Points
Saad Lulu
Saad Lulu
6,821 Points

We usually use single quotes for string that will not print out a value of a variable, and double quotes will render the value of a variable.

<?php
$string = 'hello world';
echo 'I said $string'; // I said $string
echo "I said $string" // I said hello world
?>

if you want to use single quotes but also get a value of a variable you can use concatination like so,

<?php
  $string = 'Hello world'
  echo 'I said' . $string; // I said Hello world
?>
Yaxin Yuan
Yaxin Yuan
11,191 Points

sry, just found that I did not type the code properly, and it wasn't displayed.

vickiecomrie
vickiecomrie
3,248 Points
vickiecomrie
vickiecomrie
3,248 Points

You can also use '' and "" interchangeably-- for example

<?php $string="vick"; echo 'I said $string'; echo "I said $string"; ?>

I said $stringI said vick