upload file button

with image preview

by Imri Paloja

HTML

<input type="file" style="display:none" id="upload-image" multiple="multiple"></input>
<div id="upload" class="drop-area">
   Upload File
</div>
<div id="thumbnail"></div>
<ul>
    <li><a href="http://blog.revathskumar.com/2012/04/html5-show-thumbnail-preview-of-image.html
">show-thumbnail-preview-of-image</a></li>
    <li><a href="http://www.onlywebpro.com/demo/file_reader/reader01.html">www.onlywebpro.com/demo/file_reader/reader01.html</a></li>
    <li></li>
</ul>

CSS

.drop-area{
  width:100px;
  height:25px;
  border: 1px solid #999;
  text-align: center;
  padding:10px;
  cursor:pointer;
}
#thumbnail img{
  width:100px;
  height:100px;
  margin:5px;
}
canvas{
  border:1px solid red;
}

JavaScript

jQuery(function($){
var fileDiv = document.getElementById("upload");
var fileInput = document.getElementById("upload-image");
console.log(fileInput);
fileInput.addEventListener("change",function(e){
  var files = this.files
  showThumbnail(files)
},false)

fileDiv.addEventListener("click",function(e){
  $(fileInput).show().focus().click().hide();
  e.preventDefault();
},false)

fileDiv.addEventListener("dragenter",function(e){
  e.stopPropagation();
  e.preventDefault();
},false);

fileDiv.addEventListener("dragover",function(e){
  e.stopPropagation();
  e.preventDefault();
},false);

fileDiv.addEventListener("drop",function(e){
  e.stopPropagation();
  e.preventDefault();

  var dt = e.dataTransfer;
  var files = dt.files;

  showThumbnail(files)
},false);

function showThumbnail(files){
  for(var i=0;i<files.length;i++){
    var file = files[i]
    var imageType = /image.*/
    if(!file.type.match(imageType)){
      console.log("Not an Image");
      continue;
    }

    var image = document.createElement("img");
    // image.classList.add("")
    var thumbnail = document.getElementById("thumbnail");
    image.file = file;
    thumbnail.appendChild(image)

    var reader = new FileReader()
    reader.onload = (function(aImg){
      return function(e){
        aImg.src = e.target.result;
      };
    }(image))
    var ret = reader.readAsDataURL(file);
    var canvas = document.createElement("canvas");
    ctx = canvas.getContext("2d");
    image.onload= function(){
      ctx.drawImage(image,100,100)
    }
  }
}
          });