Can I read a local json, image or text file from Javascript?

In javascript they are giving support to read the file bytes and so you can render it on your page using following events.

• FileReader.readAsArrayBuffer(): It contains an ArrayBuffer representing the file’s data.
• FileReader.readAsBinaryString(): It contains the raw binary data from the file as a string.
• FileReader.readAsDataURL(): It contains a URL representing the file’s data.
• FileReader.readAsText(): It contains the contents of the file as a text string with default encoding in UTF-8 Format. [This is usable for your case]`

Use the following code to set preview for your uploaded file.

<input type="file" name="inputfile" id="inputfile">

Show your text file data in 'pre' tag.

<pre id="result"></pre>

Your javascript function and its usage: Input Text file.

<script type="text/javascript">
 document.getElementById('inputfile').addEventListener('change', function() {

 var fr=new FileReader();
 fr.onload=function(){
 document.getElementById('result').textContent=fr.result;
 }

 fr.readAsText(this.files[0]);
 });
</script>

Reference: Mozilla

Hope it will helpful for you.