The readAsText method is used to read the contents of the specified Blob or File. When the read operation is complete, the readyState is changed to DONE, the loadend event is triggered, and the result attribute contains the contents of the file as a text string.
Syntax
instanceOfFileReader.readAsText(blob[, encoding]);
Parameters
blob- The
BloborFilefrom which to read. - encoding Optional
- A string specifying the encoding to use for the returned data. By default, UTF-8 is assumed if this parameter is not specified.
Specifications
| Specification | Status | Comment |
|---|---|---|
| File API The definition of 'FileReader' in that specification. |
Working Draft | Initial definition |
Browser compatibility
We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!
| Feature | Firefox (Gecko) | Chrome | Edge | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|---|
| Basic support | 3.6 (1.9.2)[1] | 7 | (Yes) | 10[2] | 12.02[3] | 6.0.2 |
| Feature | Firefox Mobile (Gecko) | Android | Edge | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|
| Basic support | 32 | 3 | (Yes) | 10 | 11.5 | 6.1 |
[1] Prior to Gecko 2.0 beta 7 (Firefox 4.0 beta 7), all Blob parameters below were File parameters; this has since been updated to match the specification correctly. Prior to Gecko 13.0 (Firefox 13.0 / Thunderbird 13.0 / SeaMonkey 2.10) the FileReader.error property returned a FileError object. This interface has been removed and FileReader.error is now returning the DOMError object as defined in the latest FileAPI draft.
[2] IE9 has a File API Lab.
[3] Opera has partial support in 11.1.