File object in javascript

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Copyright by Refsnes Data. All Rights Reserved. Avoid String , Number , and Boolean objects. They complicate your code and slow down execution speed. Alert "John" by extracting information from the person object. We just launched W3Schools videos. Get certified by completing a course today! If you want to report an error, or if you want to make a suggestion, do not hesitate to send us an e-mail:. Object Properties Methods car. Example1 person. Evestigneev you've misinterpreted the results as the supported browsers have a global use of around 0.

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New post summary designs on greatest hits now, everywhere else eventually. Linked 0. See more linked questions. Related Hot Network Questions. Question feed. Stack Overflow works best with JavaScript enabled. Blob data is stored in the memory or filesystem depending on the browser and blob size.

A blob can be used like a file wherever we use files. Most APIs for working with blobs are asynchronous. Content of a blob can be read as ArrayBuffer and therefore it makes blobs very handy to store binary data. A blob can be created using Blob class. In the above code we saw how we can insert data to a blob. We can read data from a blob using FileReader Class. We can retrieve remote files using AJAX and and store the file data inside a blob.

We can get the blob content in an ArrayBuffer and then analyze the ArrayBuffer as binary data. This can be done using FileReader.