title: How can I convert the blob url into blob object via Javascript?
body: <p>I try to use the blob url to display the image file on the front view and sent the data to other module via javascript like this:</p>
  
  <pre><code>for (var i = 0; i &lt; files.length; i++) {
            var imagefile_url = window.URL.createObjectURL(files[i]);
            originFiles.push(imagefile_url);
            imageFiles[i] = new Promise(resolve =&gt;{
              _this.autoCropImage(imagefile_url, function(imgData, blob){
                resolve({blobOBJ: blob, cropped:imgData}); //blob is blob object file and imgData is blob url
              });
            })
          }
          Promise.all(imageFiles).then(value=&gt;{
            _this.props.readInputFile(value, originFiles);
          });
  </code></pre>
  
  <p>and I display the image file by <code>&lt;img scr={this.state.cropped}&gt;</code>.
  But when I want to upload the image file to imgur, I need to convert the <code>blob url</code> back to <code>blob object</code>.
  I use the way to get the blob object is using the state temporary to save the blob object.</p>
  
  <p>As following my code is <code>formdata.append("image", this.state.blobOBJ)</code>, but I want to use only one <code>key(this.state.cropped)</code>.</p>
  
  <p>Is there the way to convert blob url into blob object?</p>