使用php将字符串替换为基于n次出现的单词

Question

I have a string with anchor tags i filtered the string and got all anchor tags and value.

my array will be :

Array 
(
  [www.google.com] = Array 
      (
        [0]=> click here
        [1]=> search engine
      }
  [http://www.gmail.com] => Array
    (
     [0] => text1
     [1] => 
     [2] => text2
     [3] => 
    )
)

Now i want to replace the link basing on occurrence. Here 0,1,2 .. represents occurrence of a string. What should i do if i want to replace 3rd occurrence of gmail link.

How to replace a string basing on its occurrence? Can anyone help me out of this ?

Answer 1

If I am understanding it seems like this would work:

foreach(array_keys($array_of_anchors) as $anchor_text) {
    if(count($array_of_anchors[$anchor_text]) > 2) {
        $array_of_anchors[$anchor_text][2] = //do replace   
    }
}

A simple loop to search through each anchor, see if there are more than 2 occurrences and then do whatever you want with the 2 index (3rd occurrence) in the array.

Answer 2

Your question is not very clear, but if you only want to replace the * x *th occurrence of a string you can replace all x occurrences then undo x - 1 . Assuming $target is your string, $search is what you're looking for, and $replace is the replacement then you could try:

str_replace($search, $replace, $target, $x); 
str_replace($replace, $search, $target, ($x - 1));

But, be careful, this will go wrong if there was an occurrence of the $replace string already in $target . To be really safe you should check for $replace first. This also works for preg_replace .

Alternatively you could do preg_match in a loop, counting the matches and moving the offset forward through the string. Then when the count matches what you want do preg_replace to replace that one.

If you're working with HTML it might be better to try and parse as a structured document rather than using search/replace.

Answer 3

I figured out the solution for my problem instead replacing all search words at once using offset position. Its better to replace one after the other in sequential manner which helps in resolving the problem.

protected  function replaceLinkWithShortUrl($content,$toReplace,$search){
        $pos = strpos($content,$search);
        $replacedContent = substr_replace($content, $toReplace, $pos).substr($content, $pos+strlen($search));
        return $replacedContent;
    }

Above code will search for a word in content and replace with a value and append the content again. This procedure will repeat untill replacing all search key's with values.

Thank you guys for those who helped me in resolving the problem. Thank you SpaceDog..