<businesses>
    <entity name="Retail">
      <description>Products and items available in retail</description
+>
      <product min="0" max="3">
          <description>Product information</description>
        <item name="Title">
          <description>Title</description>
          <text maxlength="80" size="65" />
        </item>
      </product>
    </entity>
    <item name="Patrol">
          <description>Title</description>
          <text maxlength="80" size="65" />
    </item>
    <entity name="Sports">
      <description>Sports Items</description>
      <product min="0" max="3">
        <item name="Title">
          <description>Title</description>
          <text maxlength="80" size="65" />
        </item>
      </product>
    </entity>
</businesses>
[download]

Target

<businesses>
    <block name="Retail" min="0" max="3">
      <description>Products and items available in retail</description
+>
          <description>Product information</description>
        <item name="Title">
          <description>Title</description>
          <text maxlength="80" size="65" />
        </item>
    </block>
    <item name="Patrol">
          <description>Title</description>
          <text maxlength="80" size="65" />
    </item>
    <block name="Sports" min="0" max="3">
      <description>Sports Items</description>
        <item name="Title">
          <description>Title</description>
          <text maxlength="80" size="65" />
        </item>
    </block>
</businesses>
[download]

This is the code snippet attempting the conversion.

It converts the begining tags(e.g cited below) for the first instance (conversion must happen at every occurance)

<entity name="Retail">
      <description>Products and items available in retail</description
+>
      <product min="0" max="3">
[download]

To

    
<block name="Retail" min="0" max="3">
      <description>Products and items available in retail</description
+>
[download]

Also the corresponding end tags need to be replaces as below

      </product>
    </entity>
[download]

To

    
    </block>
[download]

Please Advice.

    
########### Process the Input string ############
my $replstr ="<block ";
## The $strFile  holds the source string 
if($strFile =~ m/<product (.*)?>/)
{
  
  $range_rep = $1;
  $strFile =~ m/<product [^>]+>/;
  $str2relpace = "$`$&";           # This is the string to be replaced
  if($str2relpace =~ m/<\/(.*)?></)
  {
      $matchStr = "$'";
  }else
  {
      $matchStr =$str2relpace;
    }
  
  if($` =~ m/<description>.*<\/description>/)
  {
      $desc = $&;
  }

  $desc = "\n".$desc if($desc);
  $` =~ m/<item (.*)?>/;
  $elementName = $1;
  $eleVal=$1 if($elementName =~ m/\"(.*)\"/);
  
  # Constructing the replace string.
  $replstr .=$elementName." ".'location="'."$eleVal\" ". "$range_rep".
+'>';     # This is the replacing string
  
  $strFile =~ s/\Q$matchStr\E/$replstr$desc/g;   
  
  #$strFile =~ s/<\/product><\/entity>/<\/block>/ig;
  
  
  print "\n\n\n The output is ================= \n $strFile \n \n ====
+==============\n";
  
}
[download]

READMORE tags added by Arunbear