読み込んだファイルの内容を返します。このプロパティは読み込みが終了した後に有効になり、プロパティのデータ型は読込処理を行うメソッドによって変わります。
構文
var file = instanceOfFileReader.result
値
文字列または ArrayBuffer です。どちらであるかは読込処理を行うメソッドによって変わります。
仕様
| Specification | Status | Comment |
|---|---|---|
| File API The definition of 'FileReader' in that specification. |
Working Draft | Initial definition. |
ブラウザ実装状況
| Feature | Firefox (Gecko) | Chrome | Internet Explorer* | Opera* | Safari |
|---|---|---|---|---|---|
| Basic support | 3.6 (1.9.2) | 7 | 10 | 12.02 | 6.0.2 |
| Feature | Firefox Mobile (Gecko) | Android | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | 32 | 3 | 10 | 11.5 | 6.1 |
Implementation notes
- IE9 has a File API Lab.
- Opera has partial support in 11.1.
Gecko-specific notes
- Prior to Gecko 2.0 beta 7 (Firefox 4.0 beta 7), all
Blobparameters below wereFileparameters; 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.errorproperty returned aFileErrorobject. This interface has been removed andFileReader.erroris now returning theDOMErrorobject as defined in the latest FileAPI draft.