使用DropDown值存储Var,然后使用该值打开给定的html

I have a dropdown menu with the values pulled out from my sql Db.

after selecting the value, it is stored in a variable.

Lets say that i choose an option "ABC" and this is stored into the variable, i then want to use this var for opening the html file on my localhost named ABC.html

Baiscily the objectiv is redirect the user to the web page related to his choice.

here is my Script:

<html>
    <head>
    <script>
function getOption() {
    var obj = document.getElementById("choosedOP");
    document.getElementById("demo").innerHTML =
    obj.options[obj.selectedIndex].text;
}
</script>
        <title>ComboBox Ajax, PHP y MySQL</title>
        <script src="includes/js.js"></script>
    </head>

    <body onload="getOp1();">

        <div id="op1"></div> <br />

        <div id="op2"></div> <br />

        <div id="op3"></div>
        <input type="button" onclick="getOption()" value="Click Me!">
    </form>

    <p id="demo"></p>
</body>
</html>

When i click the submit button it retrieves the selected option. How can i make it to redirect to any html select by the user?

<html>
    <head>
    <script>
   
function getOption() {
            obj = document.getElementById("choosedOP");
    document.getElementById("demo").innerHTML =
    obj.options[obj.selectedIndex].text;
}
function redirect(){
 obj = document.getElementById("choosedOP");
var href = obj.options[obj.selectedIndex].text;
window.location=href;
}
</script>
        <title>ComboBox Ajax, PHP y MySQL</title>
        <script src="includes/js.js"></script>
    </head>

    <body>
    <input type="button" id="redirect" value="redirect" onclick="redirect()">
        <select id="choosedOP">
        <option>http://wiki.com</option>
        <option>https://www.wikipedia.org/</option>
        </select>
        <div id="op1"></div> <br />

        <div id="op2"></div> <br />

        <div id="op3"></div>
        <input type="button" onclick="getOption()" value="Click Me!">
    </form>

    <p id="demo"></p>
</body>
</html>

</div>
function redirect(){
 obj = document.getElementById("choosedoption");
var href = obj.options[obj.selectedIndex].text;
window.location.href = 'obj.php?=' + this.options[this.selectedIndex].value;">

Does this make any sense?