How to read local files in html

In HTML, read local files through File API. The steps include: Create a file selector using the element. Add an event listener to the file picker. In the event handler, use a FileReader object to read the file. After a successful read, the result attribute contains the file contents and can be processed as needed.

How to use HTML to read local files

In HTML, reading local files is mainly done by using the File API . The File API is a set of JavaScript APIs that allow web pages to read files from user devices.

Steps required:

1. Create a file selector using the element:

2. ##Add an event listener to the file selector:

   const input = document.querySelector('input[type="file"]');
   input.addEventListener('change', handleFileSelect);

3. Read file in event handler:

   function handleFileSelect(event) {
     const files = event.target.files;
     const reader = new FileReader();
     reader.onload = function() {
       // 读取成功后，`result` 属性将包含文件的内容。
       const content = reader.result;
   
       // 对文件内容执行所需的处理。
     };
     reader.readAsText(files[0]);
   }

Sample code:

  
  读取文件

Note:

File API only works with HTML5 browsers.
• Reading local files requires explicit authorization from the user.
• Browsers have specific restrictions on file size and type.
• Use the File API with caution as it may cause security risks.

The above is the detailed content of How to read local files in html. For more information, please follow other related articles on the PHP Chinese website!