使用现有的 js 文件变量在条件下更改雷达颜色

Question

I have a radar_box div which is color #7eb6ff, i want to change the color to red if the jsonstr value in external javascript file is above 100. my code is so far doing nothing:

html:

    <script type="text/javascript" src="../declare.js"></script>

        <section id="alert">
        <h1>alert</h1><br><br>
        <div class="radar_box_area">
            <div class="radar_box" id="radar_box">
                <div class="radar"></div>
            </div>
        </div>
        <script>
            var mmm=document.getElementById("radar_box");
            function cond(){
                if(jsonstr > 100){
                    mmm.style.backgroundColor("red");
            }}

       </script>
    </section>

my declare.js file:

var jsonstr = ["131.05\r\n"] 

if the solution is to write my condition in js file, i can't do it because declare.js is created when i run python code. so the whole file is rewritten.

Answer 1

in cond function use this snippet. what we done here is just replace any spaces , convert return str to number by using + sign and then compare with value.

var jsonstr = ["131.05\r\n"];
const check = +jsonstr[0].replace(/(\r\n|\n|\r)/gm, '')

if (check > 100) {
  console.log('in', check)
}