为什么我的JavaScript代码中的选择器功能不起作用?

时间:2017-12-14 03:41:57

标签: javascript html css

你好我正在尝试这个小练习弹出图像以创建一个模态(对话框)但是当我点击它们但没有一个能做到这一点时,我一直在查看javascript但我可以'找到问题,我的JavaScript中的选择器功能看起来没问题,还有带id的类,我很感激帮助感谢你们。

.myImg {
    border-radius: 5px;
    cursor: pointer;
    transition: 0.3s;
}

.myImg:hover {opacity: 0.7;}

/* The Modal (background) */
.modal {
    display: none; /* Hidden by default */
    position: fixed; /* Stay in place */
    z-index: 1; /* Sit on top */
    padding-top: 100px; /* Location of the box */
    left: 0;
    top: 0;
    width: 100%; /* Full width */
    height: 100%; /* Full height */
    overflow: auto; /* Enable scroll if needed */
    background-color: rgb(0,0,0); /* Fallback color */
    background-color: rgba(0,0,0,0.9); /* Black w/ opacity */
}

/* Modal Content (image) */
.modal-content {
    margin: auto;
    display: block;
    width: 80%;
    max-width: 700px;
}

/* Caption of Modal Image */
#caption {
    margin: auto;
    display: block;
    width: 80%;
    max-width: 700px;
    text-align: center;
    color: #ccc;
    padding: 10px 0;
    height: 150px;
}

/* Add Animation */
.modal-content, #caption {    
    -webkit-animation-name: zoom;
    -webkit-animation-duration: 0.6s;
    animation-name: zoom;
    animation-duration: 0.6s;
}

@-webkit-keyframes zoom {
    from {-webkit-transform:scale(0)} 
    to {-webkit-transform:scale(1)}
}

@keyframes zoom {
    from {transform:scale(0)} 
    to {transform:scale(1)}
}

/* The Close Button */
.close {
    position: absolute;
    top: 15px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    transition: 0.3s;
}

.close:hover,
.close:focus {
    color: #bbb;
    text-decoration: none;
    cursor: pointer;
}

/* 100% Image Width on Smaller Screens */
@media only screen and (max-width: 700px){
    .modal-content {
        width: 100%;
    }
}
<h2>Image Modal</h2>
<p>In this example, we use CSS to create a modal (dialog box) that is hidden by default.</p>
<p>We use JavaScript to trigger the modal and to display the current image inside the modal when it is clicked on. Also note that we use the value from the image's "alt" attribute as an image caption text inside the modal.</p>

<img id="myImg" src="https://cdn.theatlantic.com/assets/media/img/mt/2017/06/GettyImages_675371680/lead_960.jpg?1498239007" alt="Trolltunga, Norway" width="300" height="200">

<img id="myImg" src="https://cdn.theatlantic.com/assets/media/img/mt/2017/06/GettyImages_675371680/lead_960.jpg?1498239007" alt="Trolltunga, Norway" width="300" height="200">

<!-- The Modal -->
<div id="myModal" class="modal">
  <span class="close">&times;</span>
  <img class="modal-content" id="img01">
  <div id="caption"></div>
</div>


<script>
// Get the modal
var modal = document.getElementById('myModal');

// Get the image and insert it inside the modal - use its "alt" text as a caption
var img = document.getElementById('myImg');
var modalImg = document.getElementById("img01");
var captionText = document.getElementById("caption");
img.onclick = function(){
    modal.style.display = "block";
    modalImg.src = this.src;
    captionText.innerHTML = this.alt;
}

// Get the <span> element that closes the modal
var span = document.getElementsByClassName("close")[0];

// When the user clicks on <span> (x), close the modal
span.onclick = function() { 
    modal.style.display = "none";
}
</script>
<h2>Image Modal</h2>
<p>In this example, we use CSS to create a modal (dialog box) that is hidden by default.</p>
<p>We use JavaScript to trigger the modal and to display the current image inside the modal when it is clicked on. Also note that we use the value from the image's "alt" attribute as an image caption text inside the modal.</p>

<img class="myImg" src="https://cdn.theatlantic.com/assets/media/img/mt/2017/06/GettyImages_675371680/lead_960.jpg?1498239007" alt="Trolltunga, Norway" width="300" height="200">

<img class="myImg" src="https://cdn.theatlantic.com/assets/media/img/mt/2017/06/GettyImages_675371680/lead_960.jpg?1498239007" alt="Trolltunga, Norway" width="300" height="200">

<!-- The Modal -->
<div id="myModal" class="modal">
  <span class="close">&times;</span>
  <img class="modal-content" id="img01">
  <div id="caption"></div>
</div>


<script>
// Get the modal
var modal = document.getElementById('myModal');

// Get the image and insert it inside the modal - use its "alt" text as a caption
var img = document.getElementsByClassName('myImg');
var modalImg = document.getElementById("img01");
var captionText = document.getElementById("caption");
img.onclick = function(){
    modal.style.display = "block";
    modalImg.src = this.src;
    captionText.innerHTML = this.alt;
}

// Get the <span> element that closes the modal
var span = document.getElementsByClassName("close")[0];

// When the user clicks on <span> (x), close the modal
span.onclick = function() { 
    modal.style.display = "none";
}
</script>

1 个答案:

答案 0 :(得分:0)

img是一个数组而不是元素。

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// Get the modal
var modal = document.getElementById('myModal');

// Get the image and insert it inside the modal - use its "alt" text as a caption
var img = document.getElementsByClassName('myImg');
var modalImg = document.getElementById("img01");
var captionText = document.getElementById("caption");
for(var i = 0; i < img.length;i++){
  img[i].onclick = function() {
    modal.style.display = "block";
    modalImg.src = this.src;
    captionText.innerHTML = this.alt;
  }
}
// Get the <span> element that closes the modal
var span = document.getElementsByClassName("close")[0];

// When the user clicks on <span> (x), close the modal
span.onclick = function() {
  modal.style.display = "none";
}
&#13;
.myImg {
  border-radius: 5px;
  cursor: pointer;
  transition: 0.3s;
}

.myImg:hover {
  opacity: 0.7;
}


/* The Modal (background) */

.modal {
  display: none;
  /* Hidden by default */
  position: fixed;
  /* Stay in place */
  z-index: 1;
  /* Sit on top */
  padding-top: 100px;
  /* Location of the box */
  left: 0;
  top: 0;
  width: 100%;
  /* Full width */
  height: 100%;
  /* Full height */
  overflow: auto;
  /* Enable scroll if needed */
  background-color: rgb(0, 0, 0);
  /* Fallback color */
  background-color: rgba(0, 0, 0, 0.9);
  /* Black w/ opacity */
}


/* Modal Content (image) */

.modal-content {
  margin: auto;
  display: block;
  width: 80%;
  max-width: 700px;
}


/* Caption of Modal Image */

#caption {
  margin: auto;
  display: block;
  width: 80%;
  max-width: 700px;
  text-align: center;
  color: #ccc;
  padding: 10px 0;
  height: 150px;
}


/* Add Animation */

.modal-content,
#caption {
  -webkit-animation-name: zoom;
  -webkit-animation-duration: 0.6s;
  animation-name: zoom;
  animation-duration: 0.6s;
}

@-webkit-keyframes zoom {
  from {
    -webkit-transform: scale(0)
  }
  to {
    -webkit-transform: scale(1)
  }
}

@keyframes zoom {
  from {
    transform: scale(0)
  }
  to {
    transform: scale(1)
  }
}


/* The Close Button */

.close {
  position: absolute;
  top: 15px;
  right: 35px;
  color: #f1f1f1;
  font-size: 40px;
  font-weight: bold;
  transition: 0.3s;
}

.close:hover,
.close:focus {
  color: #bbb;
  text-decoration: none;
  cursor: pointer;
}


/* 100% Image Width on Smaller Screens */

@media only screen and (max-width: 700px) {
  .modal-content {
    width: 100%;
  }
}

<h2>Image Modal</h2><p>In this example,
we use CSS to create a modal (dialog box) that is hidden by default.</p><p>We use JavaScript to trigger the modal and to display the current image inside the modal when it is clicked on. Also note that we use the value from the image's "alt" attribute as an image caption text inside the modal.</p>
 <img id="myImg" src="https://cdn.theatlantic.com/assets/media/img/mt/2017/06/GettyImages_675371680/lead_960.jpg?1498239007" alt="Trolltunga, Norway" width="300" height="200"><img id="myImg" src="https://cdn.theatlantic.com/assets/media/img/mt/2017/06/GettyImages_675371680/lead_960.jpg?1498239007" alt="Trolltunga, Norway" width="300" height="200"><!-- The Modal --><div id="myModal" class="modal"><span class="close">&times;
</span><img class="modal-content" id="img01"><div id="caption"></div></div><script> // Get the modal
var modal=document.getElementById('myModal');
// Get the image and insert it inside the modal - use its "alt" text as a caption
var img=document.getElementById('myImg');
var modalImg=document.getElementById("img01");
var captionText=document.getElementById("caption");
img.onclick=function() {
  modal.style.display="block";
  modalImg.src=this.src;
  captionText.innerHTML=this.alt;
}

// Get the <span> element that closes the modal
var span=document.getElementsByClassName("close")[0];
// When the user clicks on <span> (x), close the modal
span.onclick=function() {
  modal.style.display="none";
}

</script>
&#13;
<h2>Image Modal</h2>
<p>In this example, we use CSS to create a modal (dialog box) that is hidden by default.</p>
<p>We use JavaScript to trigger the modal and to display the current image inside the modal when it is clicked on. Also note that we use the value from the image's "alt" attribute as an image caption text inside the modal.</p>

<img class="myImg" src="https://cdn.theatlantic.com/assets/media/img/mt/2017/06/GettyImages_675371680/lead_960.jpg?1498239007" alt="Trolltunga, Norway" width="300" height="200">

<img class="myImg" src="https://cdn.theatlantic.com/assets/media/img/mt/2017/06/GettyImages_675371680/lead_960.jpg?1498239007" alt="Trolltunga, Norway" width="300" height="200">

<!-- The Modal -->
<div id="myModal" class="modal">
  <span class="close">&times;</span>
  <img class="modal-content" id="img01">
  <div id="caption"></div>
</div>
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