简体   繁体   中英

How do I use single quotes inside single quotes?

Can anyone explain how to make this code work?

echo '<div id="panel1-under">Welcome <?php echo "$_SESSION['username']"; ?></div>';

I've tried removing the single quotes ( echo '<div id="panel1-under">Welcome <?php echo "$_SESSION[username]"; ?></div>'; ), but it doesn't work.

echo "<div id=\"panel1-under\">Welcome ".$_SESSION['username']."</div>";

or

echo '<div id="panel1-under">Welcome '.$_SESSION['username'].'</div>';

Quick Explain :

  • You don't have to reopen the tags inside a echo String (" ... ")
  • What I have done here is to pass the string "Welcome " concatenated to $_SESSION['username'] and "" (what the . operator does)
  • PHP is even smart enough to detect variables inside a PHP string and evaluate them :

    $variablename = "Andrew";

    echo "Hello $variablename, welcome ";

=> Hello Andrew, welcome

More infos : PHP.net - echo

Inside single quotes, variable names aren't parsed like they are inside double-quotes. If you want to use single-quoted strings here, you'll need to use the string concatenation operator, . :

echo '<div id="panel1-under">Welcome <?php echo "'.$_SESSION['username'].'"; ?></div>';

By the way: the answer to the question in the title is that in order to use a literal single-quote inside a single-quoted string, you escape the single-quote using a backslash:

echo 'Here is a single-quote: \'';

您需要连接字符串和变量。

echo '<div id="panel1-under">Welcome ' . $_SESSION['username'] . '</div>';

Variable expansion doesn't work inside of single quotes. You can do either:

echo "<div id=\"panel1-under\">Welcome {$_SESSION['username']}</div>";

or

echo '<div id="panel1-under">Welcome ' . $_SESSION['username'] . '</div>';

Generally speaking, to use the single quote inside a string that is using the single quote as delimiter, you just escape the single quote inside the string.

echo 'That\'s all, folks';

It's not clear what the purpose of your code is, though.

echo '<div id="panel1-under">Welcome <?php echo "$_SESSION['username']"; ?></div>';

As you are already using PHP code, <?php echo is not necessary. If you are trying to output the content of a session variable, you can use the following code.

echo '<div id="panel1-under">Welcome ' . $_SESSION['username'] . '</div>';

Use the following code

$data = $session['user'];
echo "a big string and $data   thats simple"

You can use double or single quotes inside double quotes.

#Result: Hello "World" 's
$a = '"World"';   
echo "Hello $a 's";

#Result: Hello "World" 's    
echo "Hello \"World\" 's";

You can also use double or single quotes inside single quotes. (Not recommended when building SQL queries)

#Result: Hello World's "s
echo 'Hello World\'s "s';

The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM