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HTML

CSS

CSS Base

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JavaScript

Babel includes JSX processing.

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HTML

              
                
  <button onclick="readFile()">Read File</button>
  <h1>Content of the newly created file:</h1>
  <span id="fileContainer"></span>


              
            
!

CSS

              
                
              
            
!

JS

              
                const _file = new File(
  ["My newly created text file"], //fileContent
  "foo.txt",                      //fileName
  { type: "text/plain" }          //fileType
);

function readFile(event){
  const reader = new FileReader();
  
  reader.onload = printResult;

  reader.readAsText(_file);
};

function printResult(e){
  const fileContainer = document.getElementById('fileContainer');
  console.log(e.target);
  fileContainer.append(e.target.result);   
}
              
            
!
999px

Console