Double Quotes vs. Single Quotes

Elizabeth

I've noticed on this board that a lot of people write their echo code with the \" instead of just a '

Example:

echo "<font size=\"2\">";

Instead of

echo "<font size='2'>";

Am I missing something?

Just curious- seems easier to read with the single quotes and less chance for error.

-Elizabeth

dcjones

Very good question Elizabeth ,

Why and whicj one is right

Dereck

christiank

Hi,

in PHP a single quote has a different meaning. If you use

echo '$myVar';

the output will be

$myVar

If you use

echo "$myVar";

the output will be the value of $myVar.

that does'nt matter in your example but

echo '<a href="$myLink" target="$myTarget">'

would not work!

Christian

tomhath

HTML is based on SGML. This is extracted from: http://www.w3.org/TR/WD-html40-970708/intro/sgmltut.html

Attributes
Elements may have associated properties, called attributes, to which authors assign values. Attribute/value pairs appear before the final ">" of an element's start tag. Any number of (legal) attribute value pairs, separated by spaces, may appear in an element's start tag. They may appear in any order.

In this example, the align attribute is set for the H1 element:

<H1 align="center">
This is a centered heading thanks to the align attribute
</H1>

By default, SGML requires you to delimit all attribute values using either double quotation marks " or single quotation marks '. Single quote marks can be included within the attribute value when the value is delimited by double quote marks, and vice versa...

In certain cases, it is possible in HTML to specify the value of an attribute without any quotation marks. The attribute value may only contain letters (a-z and A-Z), digits (0-9), hyphens (ASCII decimal 45), and periods (ASCII decimal 46). We suggest using quotation marks even when it is possible to eliminate them.

ednark

if you use ' as a delimiter you then have to \' out any real single quotes, and $variables do not get changed into their value

if you use " as your delimeter you are allowed to use ' and any $variables you write get made into it's string value, but you still must \" anytime you want a literal "... this is annoying as in php you mostly output html....

however php does have a define-your-own-delimiter syntax in which you can use ' and " and interpolate variables, only thing is you must \$ if you want a literal dollar

    $variable = 'normal string';
    print <<<XXX
      <a href="$variable">'hey there'</a>
XXX;

print <<<SOMETHINGELSE
 <font color="red">'$variable'</font>
SOMETHINGELSE;

print <<<ARBITRARYSTRING
\$variable = $variable
ARBITRARYSTRING;

$var = <<<EOS
I am \$var my value is '$value'
EOS;