javascript - 我收到错误类型错误 : Cannot read property 'addEventListener' of null-6ren

javascript - 我收到错误类型错误 : Cannot read property 'addEventListener' of null

转载作者：行者123 更新时间：2023-11-30 20:51:08

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我有以下代码片段，我不确定为什么事件监听器不工作。它给出错误:Uncaught TypeError: Cannot read property 'addEventListener' of null

var btn = document.getElementById("button");

var priceshow = document.querySelector("#price");

btn.addEventListener("click", function(){
    var XHR = new XMLHttpRequest();

    XHR.onreadystatechange = function() {
        if (XHR.readyState == 4 && XHR.status == 200) {
            var data = JSON.parse(XHR.responseText);
            var price = data.bpi.GBP.rate;
            priceshow.innerText = price;
        }
    }

    var url = "https://api.coindesk.com/v1/bpi/currentprice.json";
    XHR.open("GET", url);
    XHR.send();
}