javascript - 每 5 秒在后台检查一次远程图像

Question

我只想每 5 秒检查一次远程图像，但无法使其工作。

<script>
var img = new Image();
var url = "http://192.168.20.99/led/intro2.gif";

img.onload = function(){
    // display image or whatever you need
};
img.onerror = function(){
    alert("HOT BERRY IS NOT CONNECTED");  
    // handle the error
}
img.src = url;
 5000;
</script>

Answer 1

您可以根据您的要求使用setTimeout/setInterval。

setTimeout(function() {
   $('#test').attr("src", url);
}, 5000);

var img = new Image();
var url = "http://a9.vietbao.vn/images/vn899/55/2018/04/20180405-nu-sinh-sai-thanh-gay-sot-vi-giong-hot-girl-dep-nhat-han-quoc-1.jpg";

img.onload = function(){
    // display image or whatever you need
    setTimeout(function() {
         $('#test').attr("src", url);
      }, 5000);
};
img.onerror = function(){
    alert("HOT BERRY IS NOT CONNECTED");  
    // handle the error
}
img.src = url;

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<img id='test' width="200px"/>