Properties of String in PHP

1. Strings in PHP can either be enclose in single quotes (‘)
or double quotes (“).

   $str=’Strings in PHP’;    
   $str2=”PHP”;

both of the above are valid strings in PHP.

2. Two strings can be concatenated or joined together with
the help of the “.” Dot operator.

   $str=”I Like “.”PHP”;    
   $str2=$str.” a lot!”;

Now, $str will have the string “I Like PHP a lot!”.

3. Guess what the following code will print

   $str=”String”;    
   echo “This is $str”;

I bet many of you thought that it’d print “This is $str”.
But actually it is going to print “This is String” because variables
inside (“) double quotes are evaluated in PHP. If we had used (‘)
single quotes for the string like:

   $str=”String”;    
   echo ‘This is $str’;

It’d have printed “This is $str” as variable inside (“)
single quotes are not evaluated.

4. What would you do if you have to output a string like below:

He said “Wow!”

Would you write?

   echo “He said “Wow!””;

Obviously, it won’t work.

To do this we will have to “escape” the two quotes inside the string
to tell PHP that they are a part of the string itself. How?, by using backslash
“\”.

   echo “He said ”Wow!””;

Single quotes can also be used inside a string like below:

   echo “I’ll see you”;

   echo ‘I’ll see you’;

Now let’s us have a look at an example program which illustrates all
of these properties:

<?php //strings $str="This is a double quoted string"; $str2='This is a single quoted string'; $str3="He said \"Wow\""; $str4="I'm here"; $str5='I\'m here'; //concatenating two strings $join=$str.$str2; //print the strings echo "Joined string: $join <br />"; echo "Variable inside double quoted string: $str <br />"; echo 'Variable inside single quoted string: $str <br />'; ?>