PDF links custom class and usages

PDF links created by dFlip have their own click function. But can be somewhat intercepted and customized based on the requirement.
A custom function can be launched based on the URL of the link. Works best with a link with external URLs.

Note: This customization feature can be included in the core in future – if a proper solution emerges without confusing the user.

Final Result:

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What is expected:

Clicking on links on Page 2 leads to an external URL which is intercepted. Best criteria for customization.
Clicking on links on Page 3 leads to internal URLs and is not intercepted properly. Once the value is cached by PDF.js, it no longer checks the value from the element and cannot be intercepted.

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How to customize:

Create a flipbook with custom id so that it can be extended with option variable.

<div class="_df_book" id="test_book" source="https://dearflip.com/wp-content/uploads/2020/09/dFlip-Manual-old.pdf"></div>

<script>
var option_test_book = {annotationClass:"pdf-link-class",openPage:2};
</script>

We use jQuery dynamic selector so that it works on elements created dynamically even after the code is registered.

<script>
jQuery('body').on("click",".pdf-link-class a",function(e){
    
    var link = jQuery(this);
    //make actions based on the href
    var href = link.attr("href");
    console.log(href);
    //Internal Link href is blank and has "internalLink" class added.
    //but cannot be intercepted if the link links to different page and flipbook flips. Works if the links were created on load. not after flip.

    console.log("Is internal Link? " + link.hasClass("internalLink"));

    if(href.startsWith("http") || href.indexOf("www")>-1){
        var check = confirm("You clicked on a link for: " + href + "\r Go to the link?" );
        if(check=== false){
            e.preventDefault();
            e.stopPropagation();
        }

        //add your logic here with custom urls that begin with http:
        //example: http://test/popup2
        //if(href.indexOf("popup2")>-1){};
    }
    else{
        alert("You clicked on an internal link. Going there!");
    }
});
</script>

Note: Further fine-tuning and code changes might be added as per need.