问向图像源(Img)添加查询字符串(Img)，如果它有特定的类或ID

EN

$('img.hello').attr('src',$('img.hello').attr('src')+"addedstring")

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<img class="hello" src="http://example.com/1.jpg?source=fb">

$('.hello').attr('src', function(i, src) {
    return src + '?source=fb';
});

You can try this by Jquery. Just give another class to your image tag, assume the class 
given is "abc", it should be like :

<img class="abc hello" src="http://example.com/1.jpg">

<script>

  var image_src = $('.abc').attr('src');

  if($('.abc').hasClass('hello')){
     $('.abc').append(image_src+'?source=fb');
  }