正则表达式从字符串中删除所有单个字符

Question

I need a Regular Expression to remove ALL single characters from a string, not just single letters or numbers

The string is:

"A Future Ft Casino Karate Chop ( Prod By Metro )"

it should come out as:

"Future Ft Casino Karate Chop Prod By Metro"

The expression I am using at the moment (in PHP), correctly removes the single 'A' but leaves the single '(' and ')'

This is the code I am using:

$string = preg_replace('/\b\w\b\s?/', '', $string); 

Answer 1

Try this:

(^| ).( |$)

Breakdown:

   1.  (^| )  ->  Beginning of line or space  
   2.  .      ->  Any character  
   3.  ( |$)  ->  Space or End of line

Actual code:

$string = preg_replace('/(^| ).( |$)/', '$1', $string); 

Note: I'm not familiar with the workings of PHP regex, so the code might need a slight tweak depending on how the actual regex needs declared.

As m.buettner pointed out, there will be a trailing white space here with this code. A trim would be needed to clear it out.

Edit: Arnis Juraga pointed out that this would not clear out multiple single characters a b c would filter out to b. If this is an issues use this regex:

(^| ).(( ).)*( |$)

The (( ).)* added to the middle will look for any space following by any character 0 or more times. The downside is this will end up with double spaces where a series of single characters were located.

Meaning this:

The a b c dog

Will become this:

The  dog

After performing the replacement to get single individual characters, you would need to use the following regex to locate the double spaces, then replace with a single space

( ){2}