Single or Double Quotes??

Egri

I'm reading through the manual, and I have a question about single and double quotes.

//Outputs : say cheese! You just deleted your c:\\*.*
echo 'say cheese! You just deleted your c:\\*.*'

However I'm assuming that the same would not happen if you used double quotes; would this output be correct?

//Outputs : say cheese! You just deleted your c:*.*
echo "say cheese! You just deleted your c:\\*.*"

Please notice I took out the \ in the Outputs. Normally I would just check this on my server, but I don't currently have access to it.

My next questions is this.

Here are the single quotes:

//Outputs : The $variables do not show up with single quotes
echo 'The $variables do not show up with single quotes'

So is it possible to use single quotes to read variables? Or would I have to use Double?

//Outputs : The abcdef does show up with double quotes
echo '"The " $variables "does show up with double quotes"

Is that the correct output or am I totally off the chart? If I'm off the chart could someone please correct my errors?

Thanks in advance

paulnaj

Hi Egri,

The only reason to use double-quotes would be if you absolutely need to include 'escape characters', such as \n (newline) or \t (tab) or whatever.

Lot's of php'ers use double-quotes so that they can embed variables, like ...

echo "Hello, $name"; // Won't work with single-quotes

... but for me, this is more trouble than it's worth (the only advantage is that is milliseconds quicker to write).

I would always do ...

echo 'Hello, '.$name;

The advantages of this method are readability, debug-ibility and, not so important, a tiny improvement in speed. But the clincher is when outputting HTML. What's easier to write between these two ...

echo "<table border= \"0\">";

... or ...

echo '<table border= "0">';

... ?

The only time you need to think is when you have a single-quote in the string itself, and then you need to escape it ...

echo 'My name\'s Paul.';

I'm sure there'll be a lot of people who disagree with me, though. It's all about personal preference, I suppose.

Paul.

hkarre

heres a quick "by example" article that should give you a pretty good idea what you can and cannot do with single and double quotes:

http://www.webclass.ru/eng/Tutorials/PHP/Single_and_double.html

Single quotes will take what you have put inside them as literal and output exactly what is set between them. I think when using single quotes the only character that you have to escape is the ' character itself.

Double quoted strings are parsed by the php engine for variable names.

If i were to use a variable in a single quoted string i guess i would just do the following:

echo 'The '. $variables. ' do not show up with single quotes';

As for double quotes you can just do this:

echo "The $variable do not show up with single quotes";

Hope this helps

Egri

Awesome, thanks for the "keep it simple...stupid" approach.

Both of you made perfect sense to me and anyone else that may have been wondering.