Question

i have a form like this:

<form method=post src=upload enctype="multipart/form-data">
    <input name="img1" id="img1" type="file">
    <input type="submit" value="Upload">
</form >

Please how can I valid this form using javascript so that only jpg files are uploaded. thanks for reading.

Answer 1

You can bind the onsubmit event of your form, and check if the value of your file input ends with “.jpg” or “.jpeg”, something like this:

window.onload = function () {
  var form = document.getElementById('uploadForm'),
      imageInput = document.getElementById('img1');

  form.onsubmit = function () {
    var isValid = /\.jpe?g$/i.test(imageInput.value);
    if (!isValid) {
      alert('Only jpg files allowed!');
    }

    return isValid;
  };
};

Check the above example here.