How to convert HTML to JSON?

Create a PHP document (eg pagina_com_json.php ) giving echo with content in JSON format:

<?php
echo '[
   { "UF": "BA", "pasta": "planilhas-3-2-7" },
   { "UF": "CE", "pasta": "planilhas-3-2-2" },
   { "UF": "DF", "pasta": "planilhas-3-2-3" }
]';
?>

Then you pull PHP content with Ajax, convert JSON object with JSON.parse() , mount options and insert into select :

document.addEventListener("DOMContentLoaded", function(){

   var http = false;
   http = new XMLHttpRequest();

   var url_="pagina_com_json.php";
   http.open("GET", url_, true);
   http.onreadystatechange=function(){
      if(http.readyState==4){
         var json = JSON.parse(http.responseText),
             html = '';

         json.forEach(function(e){
            html += '<option value="http://webdanfortunato.com/premiumleiloes/'+e.pasta+'">'+e.UF+'</option>';
         });

         document.querySelector("select[name='paginas']").innerHTML += html;
      }
   }
   http.send(null);

});

Initially, leave select with only the first option , others will be inserted by Ajax above:

<select name="paginas" onchange="javascript: abreJanela(this.value)">
   <option value="#" selected>Selecione o Estado</option>
</select>

Inside this file has a Json Encoded String

You can generate by php using the json_encode(); and can convert Arrays and Bank Returns

<?php
    $arr = array("MG"=>"http://site.com","SP" => "http://outro.com");
    echo json_encode($arr);
?>

The result will be as follows

{"MG":"http:\/\/site.com","SP":"http:\/\/outro.com"}

This is probably what is in this file

But as mentioned above you can create your Json Manually In this link you will find the documentation on

An example create a MyFile.json file

and put something like this

{
"estados":[
    {"UF":"MG", "LINK":"http://site.com"}, 
    {"UF":"BA", "LINK":"http://site.com"}
]
}

and so on

If I understand you want to turn JSON into HTML ...

You can create your json:

var json = [
    {UF: 'RS', link: 'http://google.com'},
    {UF: 'SP', link: 'http://google.com'},
    //...
]

Loop to read:

var op = ''
for(var i = 0; i < json.length; i++) {
    op += '<option value="' + json[i].link + '">' + json[i].UF + '</option>'
}

And use innerHTML to display:

document.getElementById('id_select').innerHTML = op