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jqueryfilefile-uploadbase64html-input

Get data from file input in JQuery

I actually have a file input and I would like to retrieve the Base64 data of the file.

I tried:

$('input#myInput')[0].files[0]

to retrieve the data. But it only provides the name, the length, the content type but not the data itself.

I actually need these data to send them to Amazon S3

I already test the API and when I send the data through html form with encode type "multipart/form-data" it works.

I use this plugin : http://jasny.github.com/bootstrap/javascript.html#fileupload

And this plugins gives me a preview of the picture and I retrieve data in the src attribute of the image preview. But when I send these data to S3 it does not work. I maybe need to encode the data like "multipart/form-data" but I don't know why.

Is there a way to retrieve these data without using an html form?

Solution

  • You can try the FileReader API. Do something like this:

    <!DOCTYPE html>
<html>
  <head>
    <script>        
      function handleFileSelect()
      {               
        if (!window.File || !window.FileReader || !window.FileList || !window.Blob) {
          alert('The File APIs are not fully supported in this browser.');
          return;
        }   
      
        var input = document.getElementById('fileinput');
        if (!input) {
          alert("Um, couldn't find the fileinput element.");
        }
        else if (!input.files) {
          alert("This browser doesn't seem to support the `files` property of file inputs.");
        }
        else if (!input.files[0]) {
          alert("Please select a file before clicking 'Load'");               
        }
        else {
          var file = input.files[0];
          var fr = new FileReader();
          fr.onload = receivedText;
          //fr.readAsText(file);
          //fr.readAsBinaryString(file); //as bit work with base64 for example upload to server
          fr.readAsDataURL(file);
        }
      }
      
      function receivedText() {
        document.getElementById('editor').appendChild(document.createTextNode(fr.result));
      }           
      
    </script>
  </head>
  <body>
    <input type="file" id="fileinput"/>
    <input type='button' id='btnLoad' value='Load' onclick='handleFileSelect();' />
    <div id="editor"></div>
  </body>
</html>