| Package | flash.utils |
| Class | public class ByteArray |
| Inheritance | ByteArray  Object |
| Implements | IDataInput, IDataOutput |
| Subclasses | ByteArrayAsset |
| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Note: The ByteArray class is for advanced developers who need to access data on the byte level.
In-memory data is a packed array (the most compact representation for the data type)
of bytes, but an instance of the ByteArray
class can be manipulated with the standard [] (array access) operators.
It also can be read and written to as an in-memory file, using
methods similar to those in the URLStream and Socket classes.
In addition, zlib, deflate, and lzma compression and decompression are supported, as well as Action Message Format (AMF) object serialization.
A ByteArray object can share its backing memory among multiple worker
instances by setting its shareable property to true.
Possible uses of the ByteArray class include the following:
- Creating a custom protocol to connect to a server.
- Writing your own URLEncoder/URLDecoder.
- Writing your own AMF/Remoting packet.
- Optimizing the size of your data by using data types.
- Working with binary data loaded from a file.
More examples
Related API Elements
Hide Inherited Public Properties
Show Inherited Public Properties| Property | Defined By | ||
|---|---|---|---|
| bytesAvailable : uint [read-only]
The number of bytes of data available for reading
from the current position in the byte array to the
end of the array. | ByteArray | ||
 | constructor : Object
A reference to the class object or constructor function for a given object instance. | Object | |
| defaultObjectEncoding : uint [static]
Denotes the default object encoding for the ByteArray class to use for a new ByteArray instance. | ByteArray | ||
| endian : String
Changes or reads the byte order for the data; either Endian.BIG_ENDIAN or
Endian.LITTLE_ENDIAN. | ByteArray | ||
| length : uint
The length of the ByteArray object, in bytes. | ByteArray | ||
| objectEncoding : uint
Used to determine whether the ActionScript 3.0, ActionScript 2.0, or ActionScript 1.0 format should be
used when writing to, or reading from, a ByteArray instance. | ByteArray | ||
| position : uint
Moves, or returns the current position, in bytes, of the file
pointer into the ByteArray object. | ByteArray | ||
| shareable : Boolean
Specifies whether the underlying memory of the byte array is
shareable. | ByteArray | ||
| Method | Defined By | ||
|---|---|---|---|
Creates a ByteArray instance representing a packed array of bytes, so that you can use the methods and properties in this class to optimize your data storage and stream. | ByteArray | ||
In a single atomic operation, compares an integer value in this
byte array with another integer value and, if they match, swaps those
bytes with another value. | ByteArray | ||
In a single atomic operation, compares this byte array's length with a
provided value and, if they match, changes the length of this byte array. | ByteArray | ||
Clears the contents of the byte array and resets the length
and position properties to 0. | ByteArray | ||
Compresses the byte array. | ByteArray | ||
Compresses the byte array using the deflate compression algorithm. | ByteArray | ||
|
Indicates whether an object has a specified property defined. | Object | |
Decompresses the byte array using the deflate compression algorithm. | ByteArray | ||
|
Indicates whether an instance of the Object class is in the prototype chain of the object specified
as the parameter. | Object | |
|
Indicates whether the specified property exists and is enumerable. | Object | |
Reads a Boolean value from the byte stream. | ByteArray | ||
Reads a signed byte from the byte stream. | ByteArray | ||
Reads the number of data bytes, specified by the length parameter, from the byte stream. | ByteArray | ||
Reads an IEEE 754 double-precision (64-bit) floating-point number from the byte stream. | ByteArray | ||
Reads an IEEE 754 single-precision (32-bit) floating-point number from the byte stream. | ByteArray | ||
Reads a signed 32-bit integer from the byte stream. | ByteArray | ||
Reads a multibyte string of specified length from the byte stream using the
specified character set. | ByteArray | ||
readObject():*
Reads an object from the byte array, encoded in AMF
serialized format. | ByteArray | ||
Reads a signed 16-bit integer from the byte stream. | ByteArray | ||
Reads an unsigned byte from the byte stream. | ByteArray | ||
Reads an unsigned 32-bit integer from the byte stream. | ByteArray | ||
Reads an unsigned 16-bit integer from the byte stream. | ByteArray | ||
Reads a UTF-8 string from the byte stream. | ByteArray | ||
Reads a sequence of UTF-8 bytes specified by the length
parameter from the byte stream and returns a string. | ByteArray | ||
|
Sets the availability of a dynamic property for loop operations. | Object | |
Provides an overridable method for customizing the JSON encoding of values in an ByteArray object. | ByteArray | ||
|
Returns the string representation of this object, formatted according to locale-specific conventions. | Object | |
Converts the byte array to a string. | ByteArray | ||
Decompresses the byte array. | ByteArray | ||
|
Returns the primitive value of the specified object. | Object | |
Writes a Boolean value. | ByteArray | ||
Writes a byte to the byte stream. | ByteArray | ||
Writes a sequence of length bytes from the
specified byte array, bytes,
starting offset(zero-based index) bytes
into the byte stream. | ByteArray | ||
Writes an IEEE 754 double-precision (64-bit) floating-point number to the byte stream. | ByteArray | ||
Writes an IEEE 754 single-precision (32-bit) floating-point number to the byte stream. | ByteArray | ||
Writes a 32-bit signed integer to the byte stream. | ByteArray | ||
Writes a multibyte string to the byte stream using the specified character set. | ByteArray | ||
Writes an object into the byte array in AMF
serialized format. | ByteArray | ||
Writes a 16-bit integer to the byte stream. | ByteArray | ||
Writes a 32-bit unsigned integer to the byte stream. | ByteArray | ||
Writes a UTF-8 string to the byte stream. | ByteArray | ||
Writes a UTF-8 string to the byte stream. | ByteArray | ||
bytesAvailable | property |
bytesAvailable:uint [read-only] | Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
The number of bytes of data available for reading from the current position in the byte array to the end of the array.
Use the bytesAvailable property in conjunction
with the read methods each time you access a ByteArray object
to ensure that you are reading valid data.
Implementation
public function get bytesAvailable():uintdefaultObjectEncoding | property |
defaultObjectEncoding:uint| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Denotes the default object encoding for the ByteArray class to use for a new ByteArray instance.
When you create a new ByteArray instance, the encoding on that instance starts
with the value of defaultObjectEncoding.
The defaultObjectEncoding property is initialized to ObjectEncoding.AMF3.
When an object is written to or read from binary data, the objectEncoding value
is used to determine whether the ActionScript 3.0, ActionScript2.0, or ActionScript 1.0 format should be used. The value is a
constant from the ObjectEncoding class.
Implementation
public static function get defaultObjectEncoding():uint public static function set defaultObjectEncoding(value:uint):voidRelated API Elements
endian | property |
endian:String| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Changes or reads the byte order for the data; either Endian.BIG_ENDIAN or
Endian.LITTLE_ENDIAN.
The default value is BIG_ENDIAN.
Implementation
public function get endian():String public function set endian(value:String):voidRelated API Elements
length | property |
length:uint| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
The length of the ByteArray object, in bytes.
If the length is set to a value that is larger than the current length, the right side of the byte array is filled with zeros.
If the length is set to a value that is smaller than the current length, the byte array is truncated.
Implementation
public function get length():uint public function set length(value:uint):voidobjectEncoding | property |
objectEncoding:uint| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Used to determine whether the ActionScript 3.0, ActionScript 2.0, or ActionScript 1.0 format should be used when writing to, or reading from, a ByteArray instance. The value is a constant from the ObjectEncoding class.
Implementation
public function get objectEncoding():uint public function set objectEncoding(value:uint):voidRelated API Elements
position | property |
position:uint| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Moves, or returns the current position, in bytes, of the file pointer into the ByteArray object. This is the point at which the next call to a read method starts reading or a write method starts writing.
Implementation
public function get position():uint public function set position(value:uint):voidshareable | property |
shareable:Boolean| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 11.5, AIR 3.5 |
Specifies whether the underlying memory of the byte array is
shareable. For a shareable byte array, all ByteArray instances
in all workers that reference the byte array use the same underlying
system memory. The default value is false, indicating that
the underlying memory is not shared among workers.
This property also affects what the runtime does with this byte array if
it is passed to a worker using the Worker.setSharedProperty()
method or the MessageChannel.send() method:
- Not shareable: If this property is
false, when the byte array is passed to a worker the runtime creates a complete copy of the byte array, including allocating a new segment of memory in which to store the duplicate byte array's contents - Shareable: If this property is
true, when the byte array is passed to a worker the runtime uses the same underlying memory as the storage buffer for the contents of both the original ByteArray instance and the new ByteArray instance created for the second worker. In essence, both ByteArray instances contain a reference to the same underlying byte array.
The ability to access a shared byte array from multiple workers simultaneously can result in an undesirable situation where both workers are manipulating the byte array's underlying memory at the same time. You can use several mechanisms to control access to shared memory:
- the compare-and-swap mechanisms provided by the ByteArray class's
atomicCompareAndSwapIntAt()andatomicCompareAndSwapLength()methods - the specialized mechanisms provided by the Mutex and Condition classes (in the flash.concurrent package)
Setting this property to true only affects subsequent
code that passes this byte array to a worker. Any copy of this byte
array that has already been passed to a worker continues to exist as a
separate copy.
If you set this property to false when it is previously
true, the underlying memory for the byte array is
immediately copied into a new segment of system memory. This ByteArray
instance then uses the new underlying memory from that point on.
Consequently, this byte array's underlying memory is no longer shared
with other workers even if it was previously shared. If you subsequently
pass this byte array to a worker, its underlying memory is copied as
with any ByteArray object whose shareable property is
false.
The default value is false.
Implementation
public function get shareable():Boolean public function set shareable(value:Boolean):voidRelated API Elements
ByteArray | () | Constructor |
public function ByteArray()| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Creates a ByteArray instance representing a packed array of bytes, so that you can use the methods and properties in this class to optimize your data storage and stream.
atomicCompareAndSwapIntAt | () | method |
public function atomicCompareAndSwapIntAt(byteIndex:int, expectedValue:int, newValue:int):int| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 11.5, AIR 3.5 |
In a single atomic operation, compares an integer value in this byte array with another integer value and, if they match, swaps those bytes with another value.
This method is intended to be used with a byte array whose underlying
memory is shared between multiple workers (the ByteArray instance's
shareable property is true). It performs the
following sequence of steps:
- Reads an integer value from this byte array starting at the index
(measured in bytes) specified in the
byteIndexargument - Compares the actual value from this byte array to the value passed
in the
expectedValueargument - If the two values are equal, it writes the value in the
newValueargument into the byte array at the location specified by thebyteIndexparameter and returns the value that was previously contained in those bytes (the value read in step 1) - Otherwise, the contents of the byte array are not changed and the method returns the actual value read from the byte array
All these steps are performed in one atomic hardware transaction. This guarantees that no operations from other workers make changes to the contents of the byte array during the compare-and-swap operation.
Parameters
byteIndex:int — the index position (in bytes) from which the integer to
compare is read, and to which the newValue
value is written if the comparison results in a match.
This value must be a multiple of 4.
| |
expectedValue:int — the value that is expected to match the contents of
the byte array at the specified index
| |
newValue:int — the new value that replaces the contents of the byte
array at the specified index if the comparison results
in a match
|
int — the previous value at the specified location if the comparison
results in a match, or the actual value from the byte array if
the actual value and expected value don't match
|
Throws
ArgumentError — if the byteIndex value is not a
multiple of 4 or if it's negative
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Related API Elements
atomicCompareAndSwapLength | () | method |
public function atomicCompareAndSwapLength(expectedLength:int, newLength:int):int| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 11.5, AIR 3.5 |
In a single atomic operation, compares this byte array's length with a provided value and, if they match, changes the length of this byte array.
This method is intended to be used with a byte array whose underlying
memory is shared between multiple workers (the ByteArray instance's
shareable property is true). It does the
following:
- Reads the integer
lengthproperty of the ByteArray instance - Compares the length to the value passed in the
expectedLengthargument - If the two values are equal, it changes the byte array's length to
the value passed as the
newLengthparameter, either growing or shrinking the size of the byte array - Otherwise, the byte array is not changed
All these steps are performed in one atomic hardware transaction. This guarantees that no operations from other workers make changes to the contents of the byte array during the compare-and-resize operation.
Parameters
expectedLength:int — the expected value of the ByteArray's
length property. If the specified
value and the actual value match, the byte array's
length is changed.
| |
newLength:int — the new length value for the byte array if the
comparison succeeds
|
int — the previous length value of the ByteArray,
regardless of whether or not it changed
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Related API Elements
clear | () | method |
public function clear():void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 10, AIR 1.5, Flash Lite 4 |
Clears the contents of the byte array and resets the length
and position properties to 0. Calling this method explicitly
frees up the memory used by the ByteArray instance.
compress | () | method |
public function compress(algorithm:String):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9 |
Compresses the byte array. The entire byte array is compressed.
After the call, the length property of the ByteArray is set to the new length.
The position property is set to the end of the byte array.
You specify a compression algorithm by passing a
value (defined in the CompressionAlgorithm class) as the algorithm
parameter. The supported algorithms include the following:
The zlib compressed data format is described at http://www.ietf.org/rfc/rfc1950.txt.
The deflate compression algorithm is described at http://www.ietf.org/rfc/rfc1951.txt.
The lzma compression algorithm is described at http://www.7-zip.org/7z.html.
The deflate compression algorithm is used in several compression formats, such as zlib, gzip, some zip implementations, and others. When data is compressed using one of those compression formats, in addition to storing the compressed version of the original data, the compression format data (for example, the .zip file) includes metadata information. Some examples of the types of metadata included in various file formats are file name, file modification date/time, original file size, optional comments, checksum data, and more.
For example, when a ByteArray is compressed using the zlib algorithm,
the resulting ByteArray is structured in a specific format. Certain bytes contain
metadata about the compressed data, while other bytes contain the actual compressed
version of the original ByteArray data. As defined by the zlib compressed data
format specification, those bytes (that is, the portion containing
the compressed version of the original data) are compressed using the deflate
algorithm. Consequently those bytes are identical to the result of calling
compress(air.CompressionAlgorithm.DEFLATE)
on the original ByteArray. However, the result from
compress(air.CompressionAlgorithm.ZLIB) includes
the extra metadata, while the compress(CompressionAlgorithm.DEFLATE)
result includes only the compressed version of the original ByteArray data and nothing else.
In order to use the deflate format to compress a ByteArray instance's
data in a specific format such as gzip or zip, you cannot simply call
compress(CompressionAlgorithm.DEFLATE).
You must create a ByteArray structured
according to the compression format's specification, including the appropriate
metadata as well as the compressed data obtained using the deflate format.
Likewise, in order to decode data compressed in a format such
as gzip or zip, you can't simply call uncompress(CompressionAlgorithm.DEFLATE)
on that data. First, you must separate the metadata from the compressed data, and you can
then use the deflate format to decompress the compressed data.
Parameters
algorithm:String (default = NaN)compress(CompressionAlgorithm.DEFLATE)
has the same effect as calling the deflate() method.
Support for the lzma algorithm was added for
Flash Player 11.3 and AIR 3.3. You must have those player versions, or later, to use lzma compression.
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Related API Elements
deflate | () | method |
public function deflate():void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 10, AIR 1.5, Flash Lite 4 |
Compresses the byte array using the deflate compression algorithm. The entire byte array is compressed.
After the call, the length property of the ByteArray is set to the new length.
The position property is set to the end of the byte array.
The deflate compression algorithm is described at http://www.ietf.org/rfc/rfc1951.txt.
In order to use the deflate format to compress a ByteArray instance's
data in a specific format such as gzip or zip, you cannot simply call
deflate(). You must create a ByteArray structured
according to the compression format's specification, including the appropriate
metadata as well as the compressed data obtained using the deflate format.
Likewise, in order to decode data compressed in a format such
as gzip or zip, you can't simply call inflate()
on that data. First, you must separate the metadata from the compressed data, and you can
then use the deflate format to decompress the compressed data.
Related API Elements
inflate | () | method |
public function inflate():void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 10 |
Decompresses the byte array using the deflate compression algorithm. The byte array must have been compressed using the same algorithm.
After the call, the length property of the ByteArray is set to the new length.
The position property is set to 0.
The deflate compression algorithm is described at http://www.ietf.org/rfc/rfc1951.txt.
In order to decode data compressed in a format that uses the deflate compression algorithm,
such as data in gzip or zip format, it will not work to simply call inflate() on
a ByteArray containing the compression formation data. First, you must separate the metadata that is
included as part of the compressed data format from the actual compressed data. For more
information, see the compress() method description.
Throws
IOError — The data is not valid compressed data; it was not compressed with the
same compression algorithm used to compress.
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Related API Elements
readBoolean | () | method |
public function readBoolean():Boolean| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads a Boolean value from the byte stream. A single byte is read,
and true is returned if the byte is nonzero,
false otherwise.
Boolean — Returns true if the byte is nonzero, false otherwise.
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Throws
EOFError — There is not sufficient data available
to read.
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readByte | () | method |
public function readByte():int| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads a signed byte from the byte stream.
The returned value is in the range -128 to 127.
Returnsint — An integer between -128 and 127.
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Throws
EOFError — There is not sufficient data available
to read.
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readBytes | () | method |
public function readBytes(bytes:ByteArray, offset:uint = 0, length:uint = 0):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads the number of data bytes, specified by the length parameter, from the byte stream.
The bytes are read into the ByteArray object specified by the bytes parameter,
and the bytes are written into the destination ByteArray starting at the position specified by offset.
Parameters
bytes:ByteArray — The ByteArray object to read data into.
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offset:uint (default = 0)bytes at which the read data should be written.
| |
length:uint (default = 0) |
Throws
EOFError — There is not sufficient data available
to read.
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RangeError — The value of the supplied offset and length, combined, is greater than the maximum for a uint.
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More examples
readDouble | () | method |
public function readDouble():Number| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads an IEEE 754 double-precision (64-bit) floating-point number from the byte stream.
ReturnsNumber — A double-precision (64-bit) floating-point number.
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Throws
EOFError — There is not sufficient data available
to read.
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readFloat | () | method |
public function readFloat():Number| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads an IEEE 754 single-precision (32-bit) floating-point number from the byte stream.
ReturnsNumber — A single-precision (32-bit) floating-point number.
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Throws
EOFError — There is not sufficient data available
to read.
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readInt | () | method |
public function readInt():int| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads a signed 32-bit integer from the byte stream.
The returned value is in the range -2147483648 to 2147483647.
Returnsint — A 32-bit signed integer between -2147483648 and 2147483647.
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Throws
EOFError — There is not sufficient data available
to read.
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readMultiByte | () | method |
public function readMultiByte(length:uint, charSet:String):String| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads a multibyte string of specified length from the byte stream using the specified character set.
Parameters
length:uint — The number of bytes from the byte stream to read.
| |
charSet:String — The string denoting the character set to use to interpret the bytes.
Possible character set strings include "shift-jis", "cn-gb",
"iso-8859-1", and others.
For a complete list, see Supported Character Sets.
Note: If the value for the |
String — UTF-8 encoded string.
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Throws
EOFError — There is not sufficient data available
to read.
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readObject | () | method |
public function readObject():*| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads an object from the byte array, encoded in AMF serialized format.
Returns* — The deserialized object.
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Throws
EOFError — There is not sufficient data available
to read.
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Related API Elements
readShort | () | method |
public function readShort():int| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads a signed 16-bit integer from the byte stream.
The returned value is in the range -32768 to 32767.
Returnsint — A 16-bit signed integer between -32768 and 32767.
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Throws
EOFError — There is not sufficient data available
to read.
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readUnsignedByte | () | method |
public function readUnsignedByte():uint| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads an unsigned byte from the byte stream.
The returned value is in the range 0 to 255.
Returnsuint — A 32-bit unsigned integer between 0 and 255.
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Throws
EOFError — There is not sufficient data available
to read.
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readUnsignedInt | () | method |
public function readUnsignedInt():uint| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads an unsigned 32-bit integer from the byte stream.
The returned value is in the range 0 to 4294967295.
Returnsuint — A 32-bit unsigned integer between 0 and 4294967295.
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Throws
EOFError — There is not sufficient data available
to read.
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readUnsignedShort | () | method |
public function readUnsignedShort():uint| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads an unsigned 16-bit integer from the byte stream.
The returned value is in the range 0 to 65535.
Returnsuint — A 16-bit unsigned integer between 0 and 65535.
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Throws
EOFError — There is not sufficient data available
to read.
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readUTF | () | method |
public function readUTF():String| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads a UTF-8 string from the byte stream. The string is assumed to be prefixed with an unsigned short indicating the length in bytes.
ReturnsString — UTF-8 encoded string.
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Throws
EOFError — There is not sufficient data available
to read.
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Related API Elements
readUTFBytes | () | method |
public function readUTFBytes(length:uint):String| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Reads a sequence of UTF-8 bytes specified by the length
parameter from the byte stream and returns a string.
Parameters
length:uint — An unsigned short indicating the length of the UTF-8 bytes.
|
String — A string composed of the UTF-8 bytes of the specified length.
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Throws
EOFError — There is not sufficient data available
to read.
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toJSON | () | method |
public function toJSON(k:String):*| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 11, AIR 3, Flash Lite 4 |
Provides an overridable method for customizing the JSON encoding of values in an ByteArray object.
The JSON.stringify() method looks for a toJSON() method on each object that it traverses. If the
toJSON() method is found, JSON.stringify() calls it for each value it encounters, passing in the key
that is paired with the value.
ByteArray provides a default implementation of toJSON() that simply returns the name of the class. Because the content
of any ByteArray requires interpretation, clients that wish to export ByteArray objects to JSON must provide their own implementation.
You can do so by redefining the toJSON() method on the class prototype.
The toJSON() method can return a value of any type. If it returns an object, stringify() recurses into that object.
If toJSON() returns a string, stringify() does not recurse and continues its traversal.
Parameters
k:String — The key of a key/value pair that JSON.stringify() has encountered in its traversal of this object
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* — The class name string.
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Learn more
Related API Elements
toString | () | method |
public function toString():String| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Converts the byte array to a string.
If the data in the array begins with a Unicode byte order mark, the application will honor that mark
when converting to a string. If System.useCodePage is set to true, the
application will treat the data in the array as being in the current system code page when converting.
String — The string representation of the byte array.
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uncompress | () | method |
public function uncompress(algorithm:String):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Decompresses the byte array.
After the call, the length property of the ByteArray is set to the new length.
The position property is set to 0.
The byte array must have been compressed using the same algorithm as the uncompress.
You specify an uncompression algorithm by passing a
value (defined in the CompressionAlgorithm class) as the algorithm
parameter. The supported algorithms include the following:
The zlib compressed data format is described at http://www.ietf.org/rfc/rfc1950.txt.
The deflate compression algorithm is described at http://www.ietf.org/rfc/rfc1951.txt.
The lzma compression algorithm is described at http://www.7-zip.org/7z.html.
In order to decode data compressed in a format that uses the deflate compression algorithm,
such as data in gzip or zip format, it will not work to call
uncompress(CompressionAlgorithm.DEFLATE) on
a ByteArray containing the compression formation data. First, you must separate the metadata that is
included as part of the compressed data format from the actual compressed data. For more
information, see the compress() method description.
Parameters
algorithm:String (default = NaN) |
Throws
IOError — The data is not valid compressed data; it was not compressed with the
same compression algorithm used to compress.
|
Related API Elements
writeBoolean | () | method |
public function writeBoolean(value:Boolean):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Writes a Boolean value. A single byte is written according to the value parameter,
either 1 if true or 0 if false.
Parameters
value:Boolean — A Boolean value determining which byte is written. If the parameter is true,
the method writes a 1; if false, the method writes a 0.
|
writeByte | () | method |
public function writeByte(value:int):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Writes a byte to the byte stream.
The low 8 bits of the parameter are used. The high 24 bits are ignored.
Parameters
value:int — A 32-bit integer. The low 8 bits are written to the byte stream.
|
writeBytes | () | method |
public function writeBytes(bytes:ByteArray, offset:uint = 0, length:uint = 0):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Writes a sequence of length bytes from the
specified byte array, bytes,
starting offset(zero-based index) bytes
into the byte stream.
If the length parameter is omitted, the default
length of 0 is used; the method writes the entire buffer starting at
offset.
If the offset parameter is also omitted, the entire buffer is
written.
If offset or length
is out of range, they are clamped to the beginning and end
of the bytes array.
Parameters
bytes:ByteArray — The ByteArray object.
| |
offset:uint (default = 0) | |
length:uint (default = 0) |
More examples
writeDouble | () | method |
writeFloat | () | method |
writeInt | () | method |
writeMultiByte | () | method |
public function writeMultiByte(value:String, charSet:String):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Writes a multibyte string to the byte stream using the specified character set.
Parameters
value:String — The string value to be written.
| |
charSet:String — The string denoting the character set to use. Possible character set strings
include "shift-jis", "cn-gb", "iso-8859-1", and others.
For a complete list, see Supported Character Sets.
|
writeObject | () | method |
writeShort | () | method |
public function writeShort(value:int):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Writes a 16-bit integer to the byte stream. The low 16 bits of the parameter are used. The high 16 bits are ignored.
Parameters
value:int — 32-bit integer, whose low 16 bits are written to the byte stream.
|
writeUnsignedInt | () | method |
writeUTF | () | method |
public function writeUTF(value:String):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Writes a UTF-8 string to the byte stream. The length of the UTF-8 string in bytes is written first, as a 16-bit integer, followed by the bytes representing the characters of the string.
Parameters
value:String — The string value to be written.
|
Throws
RangeError — If the length is larger than
65535.
|
writeUTFBytes | () | method |
public function writeUTFBytes(value:String):void| Language Version: | ActionScript 3.0 |
| Runtime Versions: | AIR 1.0, Flash Player 9, Flash Lite 4 |
Writes a UTF-8 string to the byte stream. Similar to the writeUTF() method,
but writeUTFBytes() does not prefix the string with a 16-bit length word.
Parameters
value:String — The string value to be written.
|
ByteArrayExample to write a Boolean
and the double-precision floating-point representation of pi to a byte array. This is accomplished
using the following steps:
- Declare a new ByteArray object instance
byteArr. - Write the byte-equivalent value of the Boolean
falseand then check the length and read it back. - Write the double-precision floating-point equivalent of the mathematical value of pi.
- Read back each of the nine bytes written into the byte array.
Note: when trace() is called on a byte, it prints the decimal equivalent
of the bytes stored in the byte array.
Notice how a code segment is added at the end to check for end of file errors to ensure that the byte stream is not read past its end.
package {
import flash.display.Sprite;
import flash.utils.ByteArray;
import flash.errors.EOFError;
public class ByteArrayExample extends Sprite {
public function ByteArrayExample() {
var byteArr:ByteArray = new ByteArray();
byteArr.writeBoolean(false);
trace(byteArr.length); // 1
trace(byteArr[0]); // 0
byteArr.writeDouble(Math.PI);
trace(byteArr.length); // 9
trace(byteArr[0]); // 0
trace(byteArr[1]); // 64
trace(byteArr[2]); // 9
trace(byteArr[3]); // 33
trace(byteArr[4]); // 251
trace(byteArr[5]); // 84
trace(byteArr[6]); // 68
trace(byteArr[7]); // 45
trace(byteArr[8]); // 24
byteArr.position = 0;
try {
trace(byteArr.readBoolean() == false); // true
}
catch(e:EOFError) {
trace(e); // EOFError: Error #2030: End of file was encountered.
}
try {
trace(byteArr.readDouble()); // 3.141592653589793
}
catch(e:EOFError) {
trace(e); // EOFError: Error #2030: End of file was encountered.
}
try {
trace(byteArr.readDouble());
}
catch(e:EOFError) {
trace(e); // EOFError: Error #2030: End of file was encountered.
}
}
}
}
Mon Apr 10 2017, 12:28 PM -07:00