FileReader

open class FileReader : EventTarget(source)

The FileReader interface lets web applications asynchronously read the contents of files (or raw data buffers) stored on the user's computer, using File or Blob objects to specify the file or data to read.

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Constructors

FileReader

constructor()

Types

Companion

object Companion

ReadyState

sealed interface ReadyState

Properties

DONE

val DONE: FileReader.ReadyState

EMPTY

val EMPTY: FileReader.ReadyState

error

val error: DOMException?

The error read-only property of the FileReader interface returns the error that occurred while reading the file.

val LOADING: FileReader.ReadyState

onabort

var onabort: EventHandler<ProgressEvent, FileReader, FileReader>?

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onerror

var onerror: EventHandler<ProgressEvent, FileReader, FileReader>?

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onload

var onload: EventHandler<ProgressEvent, FileReader, FileReader>?

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onloadend

var onloadend: EventHandler<ProgressEvent, FileReader, FileReader>?

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onloadstart

var onloadstart: EventHandler<ProgressEvent, FileReader, FileReader>?

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onprogress

var onprogress: EventHandler<ProgressEvent, FileReader, FileReader>?

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readyState

val readyState: FileReader.ReadyState

The readyState read-only property of the FileReader interface provides the current state of the reading operation. This will be one of the states: EMPTY, LOADING, or DONE.

result

val result: JsAny?

The result read-only property of the FileReader interface returns the file's contents. This property is only valid after the read operation is complete, and the format of the data depends on which of the methods was used to initiate the read operation.

Functions

abort

fun abort()

The abort() method of the FileReader interface aborts the read operation. Upon return, the readyState will be DONE.

addEventListener

fun <E : Event> EventTargetLike.addEventListener(type: EventType<E>, handler: (E) -> Unit, options: AddEventListenerOptions? = undefined)

The addEventListener() method of the EventTarget interface sets up a function that will be called whenever the specified event is delivered to the target.

dispatchEvent

open fun dispatchEvent(event: Event): Boolean

The dispatchEvent() method of the EventTarget sends an Event to the object, (synchronously) invoking the affected event listeners in the appropriate order.

readAsArrayBuffer

fun readAsArrayBuffer(blob: Blob)

The readAsArrayBuffer() method of the FileReader interface is used to start reading the contents of a specified Blob or File. When the read operation is finished, the readyState property becomes DONE, and the loadend event is triggered. At that time, the result property contains an ArrayBuffer representing the file's data.

readAsDataURL

fun readAsDataURL(blob: Blob)

The readAsDataURL() method of the FileReader interface is used to read the contents of the specified Blob or File. When the read operation is finished, the readyState property becomes DONE, and the loadend event is triggered. At that time, the result attribute contains the data as a data: URL representing the file's data as a base64 encoded string.

readAsText

fun readAsText(blob: Blob, encoding: String = definedExternally)

The readAsText() method of the FileReader interface is used to read the contents of the specified Blob or File. When the read operation is complete, the readyState property is changed to DONE, the loadend event is triggered, and the result property contains the contents of the file as a text string.

removeEventListener

fun <E : Event> EventTargetLike.removeEventListener(type: EventType<E>, handler: (E) -> Unit, options: EventListenerOptions? = undefined)

The removeEventListener() method of the EventTarget interface removes an event listener previously registered with EventTarget.addEventListener() from the target.

when

fun <T : Event> when(type: EventType<T>, options: ObservableEventListenerOptions? = definedExternally): Observable<T>

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